All tools643

A Korean conscript's discharge date, days left, progress, halfway point and D-100 from the enlistment date: army 18, navy 20, air force 21 months.

Everyday

Convert a Base64 string to hexadecimal bytes and hex back to Base64, with URL-safe support, in your browser.

Developer

Encode text to MIME Quoted-Printable (RFC 2045) or decode it back — handling =XX escapes, soft line breaks and UTF-8, with 76-character wrapping.

Developer

See the exact IEEE 754 bit layout of any number in float32 and float64 — sign, exponent, mantissa, hex and rounding — or decode hex back to a number.

Convert

Enter a decimal, hex, binary or octal value and see its 8/16/32/64-bit two's complement bit pattern, with signed and unsigned readings.

Convert

Convert between decimal, binary and reflected-binary Gray code, both directions, with an optional fixed bit width and a 0-7 reference table.

Convert

Convert decimal to and from 8421 binary-coded decimal — per-digit 4-bit nibbles, packed BCD hex bytes, and BCD validity checking.

Convert

Compute xxHash32/64, MurmurHash3 (32 and 128-bit), FNV-1/FNV-1a (32 and 64-bit) and SipHash-2-4 of text, hex bytes or a file, with seeds and a key.

Developer

Hash text, hex or a file with BLAKE3 (hash, keyed, derive-key), BLAKE2b/2s with key, salt and personalization, Keccak-256/512 or SHAKE128/256.

Developer

Compute the CRC-32 (IEEE 802.3, used by zip/gzip/PNG) or CRC-32C (Castagnoli) checksum of text or hex bytes, in hex and unsigned decimal.

Developer

Compute any CRC of 3 to 64 bits — Modbus, CCITT, XMODEM, CRC-64/XZ and 108 more presets, or your own parameters — and find which CRC gives a value.

Developer

Compute and verify check digits with Luhn, Verhoeff, Damm and the ISO 7064 family (MOD 11-2, 97-10, 37-2…), and see which typing errors each one catches.

Developer

Size a Bloom filter for n items at a target false-positive rate, or get a filter's error rate or capacity, with the best number of hash functions.

Developer

Work out how many floor or wall tiles you need for a room from its length, width and the tile size, with an adjustable waste allowance and boxes required.

Everyday

Paste any UUID to see its version (1–8), variant and — for time-based v1, v6 and v7 — the embedded timestamp, clock sequence and node/MAC.

Developer

Run an XPath expression against XML or HTML in your browser and see every node it matches, with namespace prefixes and parse errors reported.

Developer

Test a CSS selector against your HTML and see exactly which elements it matches, in your browser.

Developer

Open text files in legacy encodings (EUC-KR, Shift_JIS, Windows-1252…) as readable UTF-8.

File

Open a compiled zoneinfo file in your browser: header, local time types, every transition, leap seconds and the POSIX TZ footer, parsed.

Time

Pick N winners from a list of names — cryptographically random, with or without duplicates.

Random

Split a large file into smaller chunks to bypass attachment or upload size limits.

File

Calculate the exact difference between two date-times, broken down into days, hours, minutes, and seconds.

Time

Find the average cost of shares bought at different prices and your gain or loss, and how many more to buy at today's price to reach a target average.

Everyday

Drop a ZIP and see every file inside — sizes, contents, and per-file download — without unpacking it locally.

File

Open an .epub in your browser: metadata, chapter list with word counts, the plain text, and the structure checks that explain why a reader rejects a book.

File

Paste CSV, TSV, or pipe-delimited data and get a properly aligned GitHub-flavored Markdown table.

Text

Convert a GitHub-flavored Markdown table into CSV, TSV or semicolon-separated rows, in your browser.

Text

Turn any text into a clean URL slug — strip accents, choose a separator, set a max length.

Text

Work out the fee and each payment for a Korean credit-card instalment plan from the amount, months, annual fee rate and any interest-free months.

Everyday

Generate TypeScript interfaces from any JSON sample — types are inferred recursively and named after each key.

Developer

Turn a JSON object into JSDoc @typedef blocks with @property tags, in your browser.

Developer

Transpose CSV data so rows become columns and columns become rows, in your browser.

Text

Generate realistic fake records for testing — names, emails, dates, IDs, lorem — exported as JSON, CSV, or SQL INSERTs.

Developer

Build and sign HS256 / HS384 / HS512 JWTs from a header and payload — pairs with the JWT Decoder.

Developer

Sign a message with an Ed25519 key or verify a signature in the browser, with the public key derived from the seed and R and S shown.

Developer

Generate an RSA, ECDSA, ECDH, Ed25519 or X25519 keypair in your browser and export it as PKCS#8 and SPKI PEM or as JWK.

Developer

Turn a JWK or a whole JWKS into PEM public keys and back, with the RFC 7638 thumbprint for each — computed in your browser.

Developer

Visually pick flex-direction, justify-content, align-items, and gap — copy the resulting CSS or Tailwind class.

Developer

Convert any image to ASCII art with adjustable width, character set, and inversion — all in your browser.

Image

Copy the text out of a screenshot, photo or scanned page. OCR runs in your browser in 12 languages; the image is never uploaded.

Image

Make a meme from any picture: add top and bottom captions in classic bold white outlined text and download it as PNG or JPG. Free, no watermark.

Image

Put photos side by side, stack them or arrange them in a grid, with spacing and a background colour, then download one PNG or JPG. Nothing is uploaded.

Image

Crop a photo to an exact ID size such as 35×45 mm or 2×2 in at 300 or 600 dpi, then tile it on a 4×6 in or A4 sheet to print. Nothing is uploaded.

Image

Count words, sentences, headings, links, code blocks, and estimate reading / speaking time for any Markdown.

Text

Search ISO 3166-1 country codes (alpha-2, alpha-3, numeric), ISO 4217 currencies and ISO 639-1 languages, with calling codes.

Convert

Visually pick grid-template-columns / rows, gap, and item alignment — copy the CSS straight into your project.

Developer

Type once and see how your text measures against 28+ platform limits — Twitter, Instagram, SEO titles, ad copy, app stores.

Text

Build a cron expression by clicking — hourly, daily, weekly, monthly, or fully custom — pairs with the Cron Explainer.

Developer

Convert CSV / TSV rows into SQL INSERT statements with table name, dialect quoting, type inference, and multi-row mode.

Convert

Generate the American Soundex code for names or words — a 4-character phonetic key that groups similar-sounding spellings together.

Text

Turn long words into numeronyms — first and last letter kept, the middle replaced by the count of omitted letters, as in internationalization → i18n.

Text

Spot NBSPs, zero-width characters, bidi marks, and tabs in pasted text — then clean them out.

Developer

Visually compose blur, brightness, contrast, hue, sepia, invert, and more — copy the CSS filter or Tailwind arbitrary value.

Color & CSS

Memorable, high-entropy passphrases from a curated word list — generated with Web Crypto, never sent anywhere.

Random

Split a large CSV into smaller chunks by row count — repeat the header on each chunk, download all at once.

File

Hash a password with Argon2id, Argon2i or Argon2d and get the $argon2id$ PHC string, or check a password against one. Runs in your browser.

Developer

Bulk-generate ULIDs, NanoIDs, and CUID2 — modern UUID alternatives that are shorter, sortable, or collision-resistant.

Developer

Decode a ULID into its 48-bit creation timestamp and 80-bit randomness — Crockford Base32, case-insensitive, with ISO UTC and epoch milliseconds.

Developer

Decode a Discord, Twitter/X or Instagram Snowflake ID into its creation timestamp, worker or datacenter, and sequence — with a custom-epoch mode.

Developer

Convert iPhone HEIC photos to JPG or PNG in your browser, many at once. The photos are never uploaded, and location data is not carried over.

File

Walk a .webp file’s RIFF chunks in your browser: lossy, lossless or extended, canvas versus frame size, animation timing, alpha, ICC, Exif and XMP.

File

Escape a string for 10 contexts at once — JavaScript, JSON, HTML entities, URL, SQL, regex, Bash (single/double quote), C string, Unicode \u escapes.

Developer

Derive a key from a password with PBKDF2-HMAC in your browser — pick the hash, iteration count and output length, and read the result as hex or Base64.

Developer

Derive a key from a password with scrypt in the browser, with the memory cost worked out and the PBKDF2 and ROMix stages shown.

Developer

Derive keys with HKDF and see both halves: the PRK from extract, every T block from expand, and the OKM in hex and base64. RFC 5869 cases built in.

Developer

Compute HMAC signatures with Web Crypto — sign webhook payloads, verify API requests, hex or base64 output.

Developer

Open a Windows .ico or .cur in your browser: every size inside it, PNG or BMP payloads, hotspots, the AND mask, and any broken entry.

File

Open a .tif in your browser: byte order, the IFD chain and its pages, every directory entry, and whether the pixels sit in strips or in tiles.

File

Read a Photoshop .psd or .psb without Photoshop: canvas, colour mode, every layer with its blend, opacity, mask and group, plus the thumbnail.

File

Open a .dds texture in the browser: header flags, BC1–BC7 pixel format, the mip chain with sizes and offsets, cube faces, and a decoded preview.

File

Open a .bmp or .dib in your browser: header version, bit depth, row order, compression, colour masks, palette, and where every byte of the file goes.

File

Build a fluid font-size: clamp(...) that scales smoothly between two viewport widths — copy a one-liner.

Color & CSS

Drag corners independently, try elliptical radii, copy the CSS — with chat-bubble, pill, blob, and tab presets.

Color & CSS

Encode or decode text with the Rail Fence transposition cipher — write the message in a zigzag across a chosen number of rails and read it off row by row.

Text

Translate text into leetspeak and decode 1337 back to letters, in your browser.

Text

Translate English text into Pig Latin instantly — consonant clusters move to the end with 'ay', and capitalization and punctuation are preserved.

Text

Estimate how long it takes to read or speak a text — adjustable WPM presets for slow, average, fast readers, TED, podcast.

Text

Generate pure-CSS triangles (8 directions) using border or clip-path — copy the rule, drop it in.

Color & CSS

Strip all Markdown formatting and keep readable plain text — useful for previews, summaries, email, character counts.

Convert

Mask emails, phone numbers, credit cards, and IP addresses in any text — for screenshots, blog posts, logs.

Text

Pull every email address or URL out of a block of text, in your browser.

Text

Calculate the dew point and absolute humidity from temperature and relative humidity using the Magnus formula, with a comfort rating in °C or °F.

Everyday

From dry bulb plus relative humidity, wet bulb, dew point or humidity ratio, get every moist-air property: enthalpy, specific volume, density and more.

Science & Engineering

Calculate the wind chill — how cold the air feels — from temperature and wind speed, in metric or imperial, in your browser.

Everyday

How hot it feels: the NWS heat index, Canada's humidex and the Australian apparent temperature from air temperature, humidity and wind, with risk levels.

Everyday

Drag the control points to design a CSS easing curve — preview the motion live, copy the cubic-bezier() value.

Color & CSS

Generate a [text](#anchor) TOC from Markdown headings — bullet, numbered, or HTML output with GitHub/GitLab/simple slug styles.

Text

Count how often each word appears in your text — with stopword filtering, minimum length, and CSV export.

Text

Convert CSV to an HTML <table>, a Markdown table, or a JSON array of objects — auto-detects the delimiter.

Convert

Extract HTML <table> data into CSV, TSV or semicolon-separated rows, in your browser.

Convert

Estimate ovulation day, the fertile window and your next period from the first day of your last period and your cycle length, with the next six cycles.

Everyday

Normalize messy phone input into E.164 (+15551234567), international (+1 555 123 4567), national, and tel: URI formats.

Text

Convert HTML to clean Markdown — headings, lists, links, tables, code blocks all preserved. Useful for migrating CMS content or scraping articles.

Convert

Compute your 5 training zones from age and resting HR — pick max-HR formula (Tanaka / Fox / Gulati) and method (%MHR or %HRR / Karvonen).

Everyday

Validate an International Bank Account Number — checks country code, length, and the mod-97 checksum. Supports 75+ countries.

Everyday

Validate a card number with the Luhn checksum, detect brand (Visa/MC/Amex/etc), and check expected length. Local, no network.

Developer

Pour-over, French press, AeroPress, espresso, cold brew — calculate coffee and water amounts from any ratio with method-specific defaults.

Everyday

Scale bread recipes by baker's percentage — enter the flour weight and each ingredient as a percentage of flour to get exact grams and hydration.

Everyday

Estimate daily water needs from weight, activity, climate, and pregnancy/breastfeeding status — gives a target and a 4-block schedule.

Everyday

Validate ISBN-10 and ISBN-13 checksums and convert between the two formats. Hyphens and spaces are handled.

Developer

Calculate or verify the GS1 modulo-10 check digit for EAN-13, UPC-A and EAN-8 barcodes.

Developer

Decode 4/5/6-band axial resistors into ohm value with tolerance — interactive color picker, gold/silver multipliers and tolerances supported.

Science & Engineering

Find the nearest standard resistor in E3 to E192 for any value, and the best pair of standard resistors in series or parallel to hit it more closely.

Science & Engineering

Decode 3-digit ceramic capacitor codes (104, 473K, 4R7) into picofarads, nanofarads and microfarads, with the tolerance-letter lookup.

Science & Engineering

Solve V, I, R, P from any two known values. V=IR, P=VI, P=V²/R, P=I²R — pick which pair you have, get the other two instantly.

Science & Engineering

Compute the output voltage of a two-resistor divider, or find the R2 you need for a target output, plus current and power dissipation.

Science & Engineering

Voltage drop, load voltage and power lost in a copper or aluminium cable, DC, single- or three-phase, plus the smallest AWG or mm² size within your limit.

Science & Engineering

PCB trace width for a current and temperature rise, or the current a trace can carry, per IPC-2221 — with resistance, voltage drop and power loss.

Science & Engineering

Characteristic impedance of a PCB microstrip or stripline from its geometry, or the trace width for 50 Ω, with effective εr, delay and L and C per length.

Science & Engineering

Find capacitive reactance (Xc), inductive reactance (XL), or the LC resonant frequency, with pF–F, nH–H and Hz–GHz unit pickers.

Science & Engineering

Frequency, period, high and low time and duty cycle of a 555 astable, the pulse width of a monostable, or RA and RB for a target frequency with E24 values.

Science & Engineering

Time constant, cutoff frequency, step response and low- or high-pass gain and phase of an RC or RL circuit, plus the time to reach a voltage.

Science & Engineering

Resonant frequency of an LC circuit, or the L or C for a target frequency, with reactance and impedance; add R for Q, bandwidth and −3 dB points.

Science & Engineering

Inductance of a single-layer air-core coil from diameter, length and turns using Nagaoka's exact coefficient, or the turns needed for a target inductance.

Science & Engineering

Gain, dB, output voltage, input impedance and bandwidth of inverting, non-inverting and difference op-amp stages, or standard resistors for a target gain.

Science & Engineering

How long a battery lasts on a constant or duty-cycled load, with usable-capacity derating and Peukert's law, or the capacity a target runtime needs.

Science & Engineering

Junction, case and heat-sink temperatures from power and thermal resistances, the heat sink a part needs or the power it can shed, with regulator loss.

Science & Engineering

Size the current-limiting resistor for an LED or series string from supply voltage, forward voltage and current — with the nearest E24 value.

Science & Engineering

Convert between mass, moles, volume and molar concentration of a solution — solve for molarity, the mass to weigh out, or the volume to make up.

Science & Engineering

Calculate the molar mass and percent composition of any chemical formula, with parentheses and hydrates, in your browser.

Science & Engineering

Apply C₁V₁ = C₂V₂ to find any unknown — the stock volume to take, the final volume, or either concentration — plus the amount of solvent to add.

Science & Engineering

Convert between pH, pOH, [H⁺] and [OH⁻] at 25 °C — enter any one and get the other three, plus an acidic / neutral / basic verdict.

Science & Engineering

Solve PV = nRT for pressure, volume, moles or temperature, with Pa/kPa/bar/atm/mmHg/psi, mL/L/m³, mol/mmol and K/°C/°F units.

Science & Engineering

Work out the TCP MSS and maximum UDP payload for a given MTU, with the overhead of PPPoE, GRE, WireGuard, VXLAN and other tunnels subtracted.

Network

Compare two lists line by line: find common items, items unique to each, union or symmetric difference — in your browser.

Text

Pad whitespace, comma or tab separated rows into neatly aligned columns, in your browser.

Text

Translate text to Unicode Braille (Grade 1) and decode Braille back to text, with capital and number signs, in your browser.

Text

Generate the Collatz sequence for any positive integer — halve when even, triple-plus-one when odd — with step count, peak value and the full path to 1.

Math & Statistics

Generate the first N Fibonacci numbers with exact big-integer precision — with the last term, the running sum and the golden-ratio approximation.

Math & Statistics

Compute a^b mod m exactly for arbitrarily large integers using fast binary exponentiation, plus the modular multiplicative inverse of the base.

Math & Statistics

Estimate what any appliance costs to run — enter its wattage, hours per day and your rate per kWh to get daily, weekly, monthly and yearly energy and cost.

Everyday

Solve any triangle from three known sides and angles — SSS, SAS, ASA, AAS or the ambiguous SSA case — with area, perimeter, radii, heights and medians.

Math & Statistics

Convert any number to scientific, engineering and E-notation, with significant-figure rounding, an expanded decimal and the order of magnitude.

Convert

AND, OR, XOR, NOT and bit shifts on two integers — shown in binary, hex, unsigned and signed decimal, with selectable 8, 16, 32 or 64-bit width.

Developer

Hard-wrap text to a fixed line width, breaking at word boundaries, in your browser.

Text

Wrap each line with a prefix and suffix and join them with any separator, in your browser.

Text

Convert text to hexadecimal bytes and decode hex back to text, with UTF-8 support, in your browser.

Convert

Generate a grid of random colors in HEX, RGB or HSL — pick how many, copy any value with one click, and regenerate instantly for design inspiration.

Random

Convert an IPv4 address between dotted-decimal, 32-bit integer, hex and binary — and see whether it's private, public, loopback and more.

Network

Encode text to \uXXXX, U+XXXX or HTML entities — and decode any of those back to text. Handles emoji and astral characters.

Developer

Reverse text four ways — by characters, word order, the letters inside each word, or line order. Works with emoji and any language.

Text

Enter any one of radius, diameter, circumference or area, and instantly get the other three — with the formulas shown.

Math & Statistics

Reformat a MAC address between colon, hyphen, Cisco dot and no-separator notation — and see its unicast/multicast and universal/local type.

Network

Convert fuel economy between US MPG, Imperial MPG, litres per 100 km and kilometres per litre. Enter a value in any unit and see all the others instantly.

Convert

Convert a frequency between Hz, kHz, MHz and GHz and its period (s, ms, µs, ns) — with angular frequency (rad/s) and RPM.

Convert

Convert a musical note to its frequency in hertz, or find the nearest note and cents detune for any frequency — with adjustable A4 reference and MIDI number.

Convert

Calculate the frequency an observer hears when source or observer moves — set emitted frequency, wave speed and each velocity to get the shift.

Science & Engineering

Repeat a word, line or block of text any number of times — joined by a new line, space, comma, nothing, or your own separator.

Text

Convert pressure between pascals, kilopascals, megapascals, bar, psi, atmospheres and mmHg (Torr) — all at once.

Convert

ISA / U.S. Standard Atmosphere 1976 temperature, pressure, density, speed of sound and viscosity from −5 to 80 km, plus pressure and density altitude.

Science & Engineering

Convert oven temperatures between °C, °F and gas mark, with fan (convection) settings and heat-level names.

Convert

Convert oven temperature and time to air fryer settings (and back) — lower the temp ~20 °C / 25 °F and cook ~20% faster.

Convert

Convert energy between joules, kJ, MJ, calories, kcal, watt-hours, kWh, BTU, foot-pounds and eV — all at once.

Convert

Convert power between watts, kW, MW, horsepower (hp & PS), BTU/h, ft·lb/s, cal/s and kcal/h — all at once.

Convert

Convert force between newtons, kN, MN, dyne, gram-force, kilogram-force, ton-force, ounce-force and pound-force — all at once.

Convert

Convert torque between N·m, N·cm, kN·m, mN·m, kgf·m, kgf·cm, gf·cm, lbf·ft, lbf·in and ozf·in — all at once.

Convert

Convert data rate between bit/s, kbit/s, Mbit/s, Gbit/s, Tbit/s and B/s, kB/s, MB/s, GB/s, TB/s — all at once.

Convert

Convert density between kg/m³, g/cm³, g/mL, kg/L and lb/ft³, lb/in³, lb/gal, oz/in³, oz/gal and slug/ft³ — all at once.

Convert

Draw, sketch or doodle in your browser with a pen, highlighter, shapes and fill bucket, with undo, then save a PNG or JPG. Free, nothing uploaded.

Image

Convert luminance between cd/m² (nits), stilb, apostilb, lambert, foot-lambert and skot — all at once.

Convert

Convert magnetic flux density between tesla, millitesla, microtesla, nanotesla (gamma), kilogauss, gauss and milligauss — all at once.

Convert

Convert absorbed dose between gray and rad and equivalent dose between sievert and rem, with the weighting factor needed to cross between them.

Convert

Convert dynamic viscosity — Pa·s, poise, centipoise, reyn — and kinematic viscosity — m²/s, stokes, centistokes — with a density field to cross over.

Convert

Convert illuminance between lux, kilolux, millilux, foot-candles, phot and milliphot — all at once, with lumen-per-area equivalents.

Convert

Convert volumetric flow between m³/s, m³/h, L/s, L/min, L/h, mL/min, ft³/s, CFM, GPM, GPH, imperial gal/min and bbl/day — all at once.

Convert

Convert acceleration between m/s², cm/s² (Gal), mm/s², mGal, km/(h·s), ft/s², in/s², mph/s, kn/s and g — all at once.

Convert

Period, speeds, escape velocity and energy of an orbit around Earth, the Moon, Mars or any body, plus Hohmann transfer Δv and time between two orbits.

Science & Engineering

Δv of a multi-stage rocket from propellant, dry mass and specific impulse, with burn times and thrust-to-weight, or the propellant a target Δv needs.

Science & Engineering

Generate a deterministic, namespace-based UUID (version 5, SHA-1) from a namespace and a name — the same inputs always produce the same UUID.

Developer

Turn a JSON object into a typed Go struct with json tags, instantly in your browser.

Developer

Turn a JSON object into Python @dataclass definitions with type hints, in your browser.

Developer

Turn a JSON object into Rust structs with serde derives and type-mapped fields, in your browser.

Developer

Turn a JSON object into Kotlin data classes with typed properties, in your browser.

Developer

Turn a JSON object into C# classes with auto-property type mapping, in your browser.

Developer

Turn a JSON object into Java POJO classes with type-mapped fields, in your browser.

Developer

Turn a JSON object into a Zod validation schema with inferred types, in your browser.

Developer

Turn a JSON object into GraphQL type definitions (SDL) with scalar mapping, in your browser.

Developer

Turn a JSON object into a Mongoose schema with type-mapped paths, in your browser.

Developer

Test file paths against a glob pattern (*, **, ?, [...], {a,b}) in your browser.

Developer

Build a Conventional Commits message with type, scope, breaking change, and footers, in your browser.

Developer

Convert a CSS declaration block into a React/JS inline style object, in your browser.

Developer

Turn a JSON object into a proto3 .proto schema with typed fields and nested messages, in your browser.

Developer

Determinant, inverse, RREF and rank, transpose, product and A x = b for matrices up to 12 × 12, in exact fractions rather than rounded decimals.

Math & Statistics

Find all real and complex roots of a polynomial up to degree 30 — cubic, quartic or higher — with multiplicities, the factored form and a residual check.

Math & Statistics

Evaluate a definite integral numerically to about 13 digits — finite or infinite limits, endpoint singularities like 1/√x — with error estimate and plot.

Math & Statistics

Break a string into characters and show each codepoint, UTF-8 bytes, HTML entity, CSS escape, and Unicode block.

Text

Normalize text to NFC, NFD, NFKC or NFKD, optionally strip diacritics, and compare codepoint and byte counts across all four forms.

Text

Repair text mangled by a wrong-encoding round-trip — turn café and don’t back into café and don't, automatically and in your browser.

Text

Find and replace across a block of text. Optional regex with global, case-insensitive, multiline, and dotAll flags. Live match count.

Text

Show day of year, ISO 8601 week, quarter, Julian day, Unix timestamp, leap-year status, and year progress for any date.

Time

Resolve a relative reference against a base URI by RFC 3986, with the dot-segment trace and the browser’s answer beside it.

Network

Break a URL into protocol, host, port, path, query, and hash. Decode query parameters into a table.

Developer

Decode a data: URI to see its MIME type, encoding, size and decoded contents, in your browser.

Developer

Build a CSS animation visually — pick a preset, tweak duration/easing/iteration, see the preview, and copy the generated keyframes.

Developer

Convert a duration between human ("1h 30m"), clock (1:30:00), ISO 8601 (PT1H30M), and raw seconds/minutes/hours/days.

Time

Inspect text or a small file as offset + hex bytes + printable ASCII, like xxd or hexdump -C.

Developer

Distance, bearings and midpoint between two lat/lon points on the WGS 84 ellipsoid, or the destination from a start point, bearing and distance.

Science & Engineering

Convert latitude/longitude to UTM and MGRS and back on WGS 84, with the grid zone, band letter, meridian convergence and point scale factor.

Convert

Magnetic declination, inclination and field strength for any place, altitude and date from 2025 to 2030, with true/magnetic bearing conversion.

Science & Engineering

Interpolate between two colors in RGB, HSL, or CIELAB space. See a gradient strip of intermediate steps.

Color & CSS

Paste any CSS selector to see its (ID, class, type) specificity, per-token breakdown, and head-to-head comparison with another selector.

Developer

Generate tints (lighter), shades (darker), and tones (with gray) from any base color — 2 to 20 stops, in HEX, RGB, or HSL.

Color & CSS

Pixels ↔ physical print size at any DPI, with print presets (72 web, 150 draft, 300 photo, 600 fine art), megapixels, aspect ratio and file size estimates.

Image

Run JSONPath queries ($.store.book[*].author, $..price) against a sample document and see the matching values.

Developer

Resolve an RFC 6901 JSON Pointer like /user/roles/0 against a document — with ~0/~1 escaping, URI fragments, and a clickable list of every pointer.

Developer

Convert internationalized domains between Unicode (münchen.de) and Punycode ASCII (xn--mnchen-3ya.de).

Developer

Format a number the way each locale expects — 1,234,567.89, 1.234.567,89, $1.23M, 12 345 ₽ — and grab the matching JavaScript snippet.

Developer

Compare two strings with Levenshtein, Damerau-Levenshtein, and Hamming distance. Plus a similarity percentage you can use as a fuzzy-match threshold.

Text

Sort the keys of a JSON object alphabetically. Optionally recurse into nested objects so the whole document is canonicalized.

Developer

Flatten nested JSON into dot-notation keys, or rebuild nested JSON from flat keys — configurable delimiter and array notation, fully reversible.

Developer

Pull every link and image out of a Markdown document — inline, reference-style, autolinks — into a CSV/JSON/MD list with text, URL, and title.

Text

Build placeholder image URLs from picsum.photos — set dimensions, grayscale, blur, a seed for stable images, or a specific image ID.

Image

Encode and decode Base32 (RFC 4648), with standard and base32hex variants — useful for TOTP secrets and Crockford-style IDs.

Developer

Encode and decode Base58 with the Bitcoin, Ripple or Flickr alphabet — from UTF-8 text or raw hex, with correct leading-zero handling.

Developer

Decode any bech32 or bech32m string: human-readable part, data symbols, witness version, program and scriptPubKey — and which checksum it verifies under.

Developer

Encrypt and decrypt with AEAD_CHACHA20_POLY1305 in your browser, with the Poly1305 one-time key and the counter split shown.

Developer

Encrypt and decrypt with AES-GCM in your browser: hex key and nonce, optional AAD, selectable tag length, and the ciphertext and tag kept apart.

Developer

Encode and decode Ascii85 (Base85) from UTF-8 text or hex bytes — Adobe/PDF variant with <~ ~> delimiters, or the plain variant. All in your browser.

Developer

Encode text to Base45 and decode Base45 back to text, following RFC 9285, in your browser.

Developer

Find the MIME type for a file extension (or the other way around) and learn what each type is for.

Developer

Searchable reference for ~50 standard HTTP request, response, CORS, caching, security, and cookie headers.

Developer

Paste a cURL command — get ready-to-use JS fetch or axios code with headers, body, method, and basic auth handled.

Developer

Turn a docker run command into a docker-compose.yml — ports, volumes, environment and limits mapped for you.

Developer

Build a .service unit file for systemd — Type, Restart, User, Environment, sandboxing — plus the install and journalctl commands.

Developer

Read an SSH public key, authorized_keys or known_hosts line: algorithm, key size, SHA256 and MD5 fingerprints, comment and options.

Developer

Open a .tar, .tar.gz or .tgz and list every entry — permissions, owner, size, timestamp and link target — without extracting it.

File

Open a .ttf, .otf or .woff and read its real family name, glyph and character counts, version, licence text and embedding permissions.

File

Open a .gif and read its blocks: frame delays and disposal, loop behaviour, palettes, transparency, and how many bytes each frame really costs.

Image

Turn a clip of any video into an animated GIF in your browser. Pick the start, length, frame rate and width; the file never leaves your device.

Image

Make a video smaller, cut out a clip or remove its sound, right in your browser: pick a resolution, a quality or a target file size. Nothing is uploaded.

Image

Save video frames as JPG or PNG: the current frame, one every few seconds, or a set number spread evenly, then download a ZIP. Nothing is uploaded.

Image

Turn a sideways or upside-down video the right way up, or mirror it, in your browser. MP4s rotate instantly without re-encoding. Nothing is uploaded.

Image

Paste a DNS packet as hex or DoH base64url and read it: header flags, opcode and rcode, every record, and the EDNS0 OPT options.

Network

Paste a BIND zone file and see what it really says: every name fully qualified, the SOA explained, and the traps a parser alone will not report.

Network

Turn a DNSKEY into the DS record your registrar wants — key tag and all three digest types — or hash a name the way NSEC3 does.

Network

Turn a certificate into its TLSA records — every selector and matching type — and check an existing record against the certificate you are serving.

Network

Decode a MongoDB BSON file in your browser: every element type with its type byte, exact int64 and decimal128, and canonical or relaxed Extended JSON.

Developer

Parse a .properties file exactly as java.util.Properties.load does — separators, escapes, continuations — and see every line that will surprise you.

Developer

Disassemble a .pkl file in the browser: every opcode, the memo, the value it rebuilds, and whether loading it would run code.

Developer

Open a .pyc from __pycache__ in your browser: which CPython wrote it, timestamp or hash invalidation, the code object tree and the disassembly.

Developer

Read a .npy or .npz header in the browser: dtype, shape, byte order, field layout and a value preview, with no NumPy and no upload.

Developer

Read a .a archive in the browser: members with sizes and dates, the symbols each object defines and needs, and whether the symbol index has gone stale.

Developer

Check a JSON document against a JSON Schema in your browser. Every error gets its JSON Pointer, the line it lands on, and the keyword that failed.

Developer

Open a .jpg and read its marker segments: baseline or progressive, chroma subsampling, estimated quality, and where the bytes actually went.

Image

Open a .p7b, .p7s or .p7m in your browser: content type, certificates, CRLs, signers, algorithms and signing times. Nothing is uploaded.

Developer

Open a .p12 or .pfx in your browser: MAC and ciphers before the password, then the certificate chain, the private key, and whether they match.

Developer

Open a macOS or iOS binary in your browser: the architectures inside a universal file, segments and sections, linked dylibs, rpaths, UUID and signing.

File

Open an MP4, M4A, M4V or MOV in your browser: brands, the fast-start check, the whole box tree, every track codec and duration, and iTunes tags.

File

Paste a .gitignore and a list of paths to see which are ignored and exactly which line decided — the answer git check-ignore -v gives.

Developer

Paste a .gitattributes and a list of paths to see every attribute git ends up setting on each path, and which line — or which macro — set it.

Developer

Paste a .mailmap and a list of author identities to see what each one resolves to, which entry did it, and which people finally merge into one.

Developer

Paste your git config files and see which value wins for every key, the scope, file and line it came from, what it overrode, and which includeIf fired.

Developer

Read a compiled .class file in the browser: class file version and JDK release, access flags, constant pool, fields, methods and referenced classes.

File

Inspect a .wasm file in your browser: section sizes, imports and exports with full types, memory pages, the start function, name and producers sections.

Developer

Open a Windows .exe, .dll, .sys or .efi in your browser: architecture, subsystem, imports, exports, sections, and whether ASLR, DEP and CFG are on.

File

Read a certificate revocation list in your browser: issuer, CRL number, validity window, every revoked serial with its reason, and the signature.

Developer

Decode an OCSP response or request in your browser: status, responder, freshness, nonce, revocation reason and the certificates it carries.

Developer

Open a Linux executable, .so or .o in your browser: architecture, shared libraries it needs, build ID, and whether it is PIE, NX and RELRO hardened.

File

Work out the git object id of a blob, tree, commit or tag in both SHA-1 and SHA-256, with the header git hashes and the loose object path.

Developer

Read a .pack and .idx pair in the browser: every object with its type, size, offset, delta depth and base, totals by type and the biggest objects.

File

Read .git/index in your browser: every staged entry with its blob hash, mode and flags, conflict stages, extensions and the trailing checksum.

File

Open an .icc or .icm file and read its header, tag table, primaries, white point and tone curves. Everything is decoded in your browser.

File

Open a .sqlite or .db file in your browser and read its structure: page size, encoding, journal mode, and every table with its real row count.

File

Read a unified diff or .patch file: files touched, insertions and deletions per file, and the malformed hunks that make git apply fail.

Developer

Read an armored OpenPGP public key: full fingerprint, key ID, algorithm, size, creation and expiry dates, user IDs and subkeys.

Developer

Read a certificate signing request before you send it: subject, SANs, key size, signature algorithm, and whether its self-signature verifies.

Developer

All 147 CSS / X11 named colors with HEX, RGB, and a live swatch — searchable and grouped by hue.

Color & CSS

Type any date (ISO, RFC, Unix epoch, locale) and see it rendered in 14+ standard formats side by side.

Time

Prorate a monthly salary for a month you joined or left partway through: calendar-day, 30-day and working-day methods side by side.

Everyday

Press keys and watch them light up on an on-screen keyboard. Find dead keys, test ghosting and n-key rollover, and read key, code and keyCode values.

Everyday

Measure clicks per second over 1, 5, 10, 30 or 60 seconds, and check every mouse button, the wheel and double-click faults.

Everyday

Fill a monitor, laptop or phone screen with solid black, white, red, green and blue to find dead, hot and stuck pixels.

Everyday

See your screen resolution, physical pixels, scaling (devicePixelRatio), browser window size, refresh rate, colour depth and HDR support at a glance.

Everyday

Free online metronome: 20–300 BPM, 1 to 12 beats per bar, eighth, triplet and sixteenth subdivisions, accent and tap tempo, timed by the audio clock.

Everyday

Play a sine, square, sawtooth or triangle tone from 1 Hz to 22 kHz, on both or one channel, see the nearest note, and save it as a WAV file.

Everyday

Play white, pink or brown noise for sleep, focus or masking sounds, with a volume control, a sleep timer that fades out and WAV download.

Everyday

Test speakers and headphones in the browser: left and right channels, phase (polarity) and a 20 Hz to 20 kHz sweep, with a level meter per channel.

Everyday

Test an Xbox, PlayStation, Switch Pro or other controller in the browser: every button, trigger pressure, stick position and drift, and vibration.

Everyday

An online tuner that listens through your microphone and shows the note and how many cents off it is. Chromatic mode, standard tunings and an adjustable A4.

Everyday

Square metres to pyeong (the Korean area unit) and back, plus an apartment's exclusive and supply areas in pyeong. 1 pyeong = 400/121 m².

Everyday

Interest on a Korean term deposit or monthly savings plan, simple or monthly compound, and what you keep after the 15.4% tax, 9.5% or none.

Everyday

Work out the fee a Korean lender charges when you repay a loan early: amount × rate × remaining days ÷ fee period, free after 3 years.

Everyday

Searchable cheat sheet for DNS record types — A, AAAA, CNAME, MX, TXT, NS, SOA, PTR, SRV, CAA, DNSSEC, SVCB / HTTPS — with examples.

Network

Drop a photo and download a clean copy with EXIF, GPS, and other metadata removed — all in your browser, no upload.

Image

Paste an SRT or WebVTT file, type an offset in seconds, and get every cue shifted forward or backward.

File

Draw a random quotation from a hand-checked collection, each shown with the book, speech or letter it comes from, and copy it with one click.

Random

Paste any JSON and get a draft-07 JSON Schema that matches its shape — types inferred, formats detected, required fields filled in.

Developer

Convert between straight (") and typographic / curly (“ ”) quotes — and back — with locale-aware styles.

Text

Generate a fully fake person — name, email, phone, address, date of birth, company — for placeholder content, mockups, or test data.

Random

Drop a few files into the browser and download them as a single .zip — no upload, no install, fast compression.

File

Switch delimited text between CSV, TSV, pipe, and semicolon — with proper RFC-4180-style quoting and auto-detection.

Convert

Split fixed-width / fixed-column text into fields by column widths and export as CSV or JSON, in your browser.

Convert

Compute Body Surface Area in m² using five published formulas — Mosteller, Du Bois, Haycock, Boyd, Gehan & George — side by side.

Everyday

Fill out a form, get a ready-to-paste <meta> block — Open Graph for Facebook / LinkedIn / Slack and Twitter Card tags for X / Discord.

Developer

The full Tailwind CSS v4 default palette — 22 hues × 11 shades, 50 through 950 — with click-to-copy as Tailwind class, HEX, or rgb().

Color & CSS

Type plain text and get Unicode superscript (²) and subscript (₂) variants — paste into chat, docs, or anywhere fonts won't help you.

Text

Searchable cheat sheet for ~60 standard TCP / UDP port numbers — from 22 (SSH) and 80 (HTTP) to 6379 (Redis) and 27017 (MongoDB).

Network

Strip HTML tags from a snippet and get just the text — keeps block-level newlines, drops <script> and <style>, decodes entities.

Text

Paste a Cookie: request header or a Set-Cookie: response header and see each cookie's name, value, attributes, and warnings.

Developer

Turn a JSON array of objects into INSERT statements — PostgreSQL, MySQL, SQLite, or ANSI quoting, with an optional ON CONFLICT upsert tail.

Convert

Slide a Kelvin value and watch the black-body colour shift from warm amber to neutral white to cool blue — plus a handful of common light-source presets.

Color & CSS

Pick a coffee, tea or cola dose and see how much caffeine is still in your system now, in an hour, in six, and when it drops below the sleep threshold.

Everyday

Type an IPv4 or IPv6 address and see its class, scope (private / public / loopback / link-local), decimal value, binary, reverse-DNS notation, and /32 CIDR.

Network

Type a 5-field cron expression and see the next N times it will fire — local time, including weekday + day-of-month dual semantics.

Time

Shrink an SVG with SVGO — strip editor cruft, round coordinates, merge shapes — and see before and after side by side. Nothing is uploaded.

Image

Pull the sound track out of an MP4, WebM or MOV video and save it as MP3 or WAV, right in your browser. Nothing is uploaded.

File

Join several songs, voice notes or sound clips into one MP3 or WAV in your browser, with an optional gap or crossfade between them. Nothing is uploaded.

File

Draw, type or upload your signature, place it on any page of a PDF, and download the signed file. Runs in your browser; nothing is uploaded.

File

Paste an HTML snippet and get React-ready JSX — class becomes className, onclick becomes onClick, and void tags self-close.

Developer

Drop an image and see its pixel dimensions, simplified aspect ratio, decimal ratio, megapixels, orientation, file size, and the closest common preset.

Image

Pick N random dates between two boundaries — with options for unique-only, sorted, and weekdays-only.

Random

Flip your text upside down with rotated Unicode characters, in your browser.

Text

Convert text to fullwidth ﾑﾑﾗ for that vaporwave aesthetic look, and back again, in your browser.

Text

Build URLs by combining a base address with editable key-value query parameters — each pair toggleable, properly percent-encoded.

Network

Convert a URL query string to a JSON object and back, in your browser.

Developer

Expand RFC 6570 URI templates with your own variables — all four levels, with path, query, fragment and label operators and explode modifiers.

Network

Pick a pattern (weekly, every Nth weekday of the month, on the same day of month, every N days) and see the next N actual dates.

Time

Paste an indented list of file and folder names and get a pretty ASCII tree — the kind you'd paste into a README.

Text

Drop a file and paste an expected SHA-1 / 256 / 384 / 512 — see if the actual hash matches. Useful before installing downloaded binaries.

File

Pick two colors and see how perceptually different they are — CIE76 ΔE, CIEDE2000 ΔE, and plain RGB distance with a side-by-side swatch.

Color & CSS

Convert a JavaScript object literal ({name: 'Alice'}) to strict JSON — or strict JSON back into a tidy JS literal with unquoted keys.

Convert

Drop an image and pixelate it to any block size — block-perfect output you can use to censor a screenshot or build retro art.

Image

Split a date range into N equal intervals — get the start/end of each chunk or just the boundary dates between them.

Time

Generate batches of random IPv4, IPv6, or MAC addresses for tests and mocks — public / private / ULA / link-local / UAA / LAA scopes supported.

Random

Build an .editorconfig file with indent style, line endings, charset and common overrides, in your browser.

Developer

Paste an .editorconfig and some file paths: see the property set each file resolves to, and which section on which line decided every value.

Developer

Compute Easter Sunday for any year using the standard Gregorian computus — or the Julian (Eastern Orthodox) variant.

Time

Convert any MAC address into its modified EUI-64 interface ID and the matching IPv6 link-local address — the same form Windows / Linux compute automatically.

Network

Quick card per HTTP method (GET, POST, PUT, DELETE, PATCH, …) — safety, idempotence, cacheability, and whether request / response bodies are allowed.

Developer

Drop a CSV, see row / column counts, per-column type inference, null counts, unique counts, and full-row duplicate detection — all locally.

File

Drop an image and split it into its red, green, and blue channels — view each one isolated or as a grayscale intensity map.

Image

Convert between spreadsheet column letters and numbers — A=1, Z=26, AA=27, BC=55 — and between A1 and R1C1 cell notation.

Convert

Toggle any IPv6 address between its shorthand ::1 form and the fully-expanded 8-group representation, with reverse DNS and binary too.

Network

Round-trip between INI-style config files and JSON — supports sections, dotted nesting, comments, and value type inference.

Convert

Paste a raw email header to walk the Received hops in order, see the per-hop delay, and read off the SPF/DKIM/DMARC verdicts.

Network

Convert between LF, CRLF, and CR line endings and add or remove a UTF-8 BOM — with per-style counts so you can see how mixed the input was.

File

Convert leading indentation between tabs and spaces with a configurable tab width, in your browser.

Text

Drop an image to see its RGB and luminance distribution, with per-channel mean, median, and clip-point stats.

Image

Build an HTTP Cache-Control header from a visual checklist — freshness, revalidation, immutability, and the common presets.

Network

Draw N cards from a properly shuffled 52-card deck (optional jokers), with deck-tracking so you don't draw the same card twice.

Random

Paste a list of hex colors and sort them by hue, saturation, lightness, or perceived brightness — useful for tidying a design-token palette.

Color & CSS

Build a CSP header from per-directive source lists, with three starter presets and live warnings for the dangerous wildcards.

Network

Find the sun's elevation and azimuth for any place and time from 1900 to 2100, with shadow length and direction, air mass and an hour-by-hour table.

Science & Engineering

Drop a file to identify its true format from its magic bytes — and catch files whose extension or declared MIME type lies.

File

Compose Access-Control-* response headers from a checklist, with four presets and live warnings for the dangerous combinations.

Network

Generate uniformly-distributed random points on Earth, optionally restricted to a bounding box — with an OpenStreetMap link for each.

Random

Paste a robots.txt and a list of user-agent and path pairs to see exactly which line allows or blocks each — with longest-match precedence.

Network

Pick names or options with custom weights — like a non-uniform raffle. See each option's true probability and draw with or without replacement.

Random

Compute the sha256 / sha384 / sha512 base64 hash an inline <script> or <style> block needs to be whitelisted by a Content-Security-Policy.

Network

Reduce a photo to N levels per channel for that flat poster-art look, with optional Floyd-Steinberg dithering and per-channel level control.

Image

Compose a Strict-Transport-Security header — max-age, includeSubDomains, preload — with a live preload-list eligibility check.

Network

For any date, get the calendar and fiscal quarter (configurable fiscal-year start), days into and left in it, and the quarter's start and end dates.

Time

Pick colours in the perceptually uniform OKLCH space (lightness · chroma · hue) — and see whether each pick fits inside the sRGB display gamut.

Color & CSS

Compose a Sender Policy Framework TXT record from mechanisms, IPs and includes — with a live DNS-lookup counter and warnings.

Network

Generates printable 3×3, 4×4 or classic 5×5 BINGO cards — number mode or your own word list, free-center optional, browser-print friendly.

Random

Drop files and preview a batch rename — pattern with {n}, {name}, {ext}, {date}, plus find/replace, case modes, and collision detection.

File

Drop several images and bake them into a single PNG sprite — horizontal, vertical or grid — plus ready-to-paste CSS background-position rules.

Image

Add timezones with each participant's working hours, see the 24-hour overlap grid, and read the best meeting slot in everyone's local time.

Time

Compose a _dmarc TXT record — policy, subdomain policy, percentage rollout, alignment, rua/ruf reporting — with safety warnings.

Network

Paste CSV/TSV, click the columns you want, get them back as plain lines, CSV, quoted-comma-separated, or a ready-made SQL IN-clause.

File

Type your options, spin a colored wheel, get a winner — with optional remove-after-winning for raffles and history of the last 20 picks.

Random

Compose a Set-Cookie header from name and value plus the security attributes — SameSite, Secure, HttpOnly, Partitioned, Max-Age — with safety warnings.

Network

Drop an .eml file and read the parsed message — key headers, plain-text and HTML body parts, and a list of attachments — all in the browser.

File

Split a .mbox archive in your browser: message boundaries, decoded headers, MIME structure, threads and duplicate Message-IDs. Nothing is uploaded.

File

Add N working hours to a start datetime — skip weekends and holidays, respect a per-day work window, get the landing timestamp and a per-day breakdown.

Time

Type a yes/no question, shake the ball, get one of 20 classic answers — or swap in your own pool. Pure randomness, no judgement.

Random

Combine multiple images into one — horizontal strip or vertical stack — with alignment, gap, background color and optional uniform scaling.

Image

Pick two hex colors, get N discrete intermediate steps — in sRGB, linear RGB, OKLab or HSL — with optional easing.

Color & CSS

Strip utm_*, fbclid, gclid and 30+ other tracking params from a URL — paste, get a clean shareable link back.

Network

Convert subtitle files between SRT (SubRip) and WebVTT — auto-detects the input format, fixes timestamp punctuation, optionally strips VTT styling tags.

File

Type a birthdate, get a live ticking countdown to the next birthday — plus exact age, days since born, hours lived, and the rare golden birthday year.

Time

Play classic Rock-Paper-Scissors against a fair random opponent — keep score, track win/loss streaks, optional best-of-3/5/10 match mode.

Random

Encode username:password into the Base64 Authorization: Basic header — or paste an existing header back to see who's in it.

Network

Paste or drop a .jsonl / .ndjson file, see records as a table, filter by field:value, pick which columns to keep, and re-export as JSON or CSV.

File

Paste a list of YYYY-MM-DD dates (with optional counts) and render a GitHub-style yearly heatmap — palette, week start, streaks, hover counts.

Time

Build the Permissions-Policy header: set camera, microphone, geolocation, payment, fullscreen and 20+ other browser features by origin allowlist.

Network

Paste or drop a Markdown file, extract the YAML / TOML / JSON frontmatter into a JSON object, and see the body separately with word and char counts.

File

Convert between a Gregorian date and a Julian Day (JD), Julian Day Number (JDN), Modified Julian Day (MJD), Reduced/Truncated JD, and Unix timestamp.

Time

Pick a Referrer-Policy value and see exactly what Referer header outbound requests will send — same-origin, cross-origin HTTPS, HTTPS→HTTP downgrade.

Network

Apply rounded corners, a full circle mask, or per-corner radii to an image — preview with a checkerboard for transparency, download as PNG or JPEG.

Image

Convert between TOML (Cargo.toml, pyproject.toml, Hugo configs) and JSON — handles tables, array-of-tables, inline tables, typed scalars.

Convert

Split a long SPF, DKIM or DMARC TXT record into the 255-byte strings DNS requires, in BIND, generic zone-file, Cloudflare or Route 53 syntax.

Network

Drop a .png file and see every chunk it contains — IHDR, IDAT, tEXt metadata, IEND — with sizes, CRCs, and the critical/ancillary/safe-to-copy flags.

File

Paste a list, get it back in random order — line-, comma- or whitespace-separated input, optional seed for reproducible runs, numbered or plain output.

Random

Expand a CIDR block (10.0.0.0/24) into a list of IPs, or convert a start-end range into the smallest covering CIDR set.

Network

Format any past or future date as 2 hours ago, in 3 days or last month — in 12 locales and three styles, with numeric: auto phrasing.

Time

Define a color palette once, export to CSS custom properties, Tailwind config, SCSS, LESS, design-token JSON, SwiftUI Color, or Android colors.xml.

Color & CSS

Generate Docker-style memorable nicknames (elegant-archimedes, funny-curie) — pick a style, separator, count.

Random

Visual builder for CSS conic-gradient() — rotate angle, center position, color stops, shape preview.

Color & CSS

Apply a two-color duotone effect to any image — pick a shadow color and a highlight color, adjust midpoint and contrast, download the result.

Image

Searchable catalog of well-known URIs registered with IANA — security.txt, openid-configuration, acme-challenge and 30+ more, with RFCs.

Network

Build a valid manifest.json for a Progressive Web App — name, icons, theme color, display mode, scope — with the matching HTML <link> tags.

Developer

Upload any text file and detect its encoding — UTF-8, UTF-16 LE/BE, UTF-32, Latin-1, ASCII — with BOM detection, byte signal analysis, and a hex preview.

File

Canonicalize JSON per RFC 8785 and hash it: UTF-16 key order, ECMAScript number form, no whitespace, with a SHA-256 of the exact bytes.

Developer

Apply or generate an RFC 7386 JSON merge patch, with every change listed — including the null that deletes a key rather than setting one.

Developer

Generate an RFC 6902 JSON Patch from a source/target pair, or apply an existing patch to a document. Supports add, remove, replace, move, copy, test ops.

Developer

Look up the day of the week for any date — supports multiple dates at once, multilingual day names, ISO week numbers, day-of-year, and leap-year flag.

Time

Generate cryptographically secure random bytes in 9 output formats — hex, Base64, Base64URL, binary, decimal, C array, Python bytes, UUID v4.

Random

Find the closest CSS, Tailwind, or XKCD-survey color name for any hex/RGB input — ranked by perceptual distance in OKLab color space.

Color & CSS

Parse a .env / dotenv file with full support for single-quoted, double-quoted, multi-line, and inline-comment values.

File

Generate code_verifier + S256/plain code_challenge for OAuth 2.0 PKCE (RFC 7636).

Network

Apply Gaussian, box, or motion blur to any image directly in your browser. Adjustable radius 0-64 px, with the equivalent CSS filter string for copy-paste.

Image

Pick random emojis from 10 categories — smileys, people, animals, food, activities, travel, objects, symbols, nature, weather.

Random

Convert between latitude/longitude and geohash strings (Niemeyer 2008). Adjustable precision 1-12, with bounding box and 8 neighbor cells.

Convert

Compare grocery and shopping items by price-per-unit (price per gram, mL, or piece). Mass, volume, and count groups with imperial and metric units.

Everyday

Convert UTC to GPS week and time of week, TAI and the GPS−UTC offset, with every leap second since 1972 listed.

Time

Convert a timestamp between seconds, milliseconds, microseconds, and nanoseconds since Unix epoch.

Time

Add solid or transparent padding and an optional border around any image.

Image

Generate a downloadable .ics calendar event with title, start/end, location, attendees, recurrence and a reminder — fully RFC 5545 compliant.

File

Open an .ics invite or calendar export and read what is actually in it — every field, plus the real dates a repeating rule produces.

File

Estimate download time from file size and connection speed — or the speed required to transfer a given size within a deadline.

Network

Generate samples from uniform, normal, exponential, Poisson, Bernoulli, or triangular distributions — with histogram, summary stats, and CSV/JSON export.

Random

Generate a Material Design 3 tonal palette (tones 0–100) from any source color, with contrast against black/white and CSS/Tailwind/JSON export.

Color & CSS

Convert any UTC moment to Greenwich and Local Sidereal Time, Julian Date, Modified Julian Date and Earth rotation angle — for telescope alignment.

Time

Drop a .gpx from your GPS watch, Strava, Garmin or Komoot and see distance, elevation gain, moving time and speed, with a map and elevation profile.

File

Build or parse a DKIM DNS TXT record — paste your public key, pick selector, key type, hash and flags, and get the record plus its chunked form.

Network

Convert any image to 1-bit dithered output using Floyd-Steinberg, Atkinson, Sierra Lite or ordered Bayer patterns — for retro, e-ink or pixel art.

Image

Convert a light wavelength in nanometres (380–780 nm) to an approximate sRGB color, with a clickable rainbow bar and Fraunhofer reference lines.

Color & CSS

Generate fresh creative prompts for drawing, writing, photography, coding side-projects, or fictional world-building.

Random

Convert between decibels and linear ratios for voltage/SPL (20·log) or power (10·log), sum dB SPL sources, and look up dBV, dBu, dBm and dBFS.

Science & Engineering

Convert a musical tempo (BPM) to note durations in milliseconds — straight, dotted and triplet — for whole, half, quarter, 8th, 16th, 32nd, 64th notes.

Time

Drop a .stl file and see triangle count, bounding box, size, volume, surface area, a watertight check, and whether it fits common 3D-printer beds.

File

Paste or load a sitemap.xml or sitemap index and see URL count, size, spec compliance, and the changefreq, priority and host distributions.

Network

Paste a feed and read it: entries, dates normalised, podcast enclosures, and the problems that make readers drop or duplicate posts.

Network

Convert between RGB / hex screen colors and CMYK percentages for print — simple, GCR and UCR black generation, plus a total ink coverage readout.

Color & CSS

Convert any image to a classic halftone using variable-sized dots, squares, diamonds or lines on a rotated grid — as offset and newspaper presses do.

Image

Random key, scale, chord, tempo, time signature and technique focus for instrument practice — 15 scales, 14 chord qualities and 20 articulations.

Random

Convert between AWG, wire diameter (mm and inch), cross-section (mm² and kcmil), SWG, resistance per km for copper and aluminum, and NEC ampacity.

Convert

Moonrise, moonset and transit times for any place and date, plus the Moon's altitude, azimuth, distance and illuminated fraction at a chosen moment.

Time

Paste or upload GeoJSON and get RFC 7946 validation, per-geometry counts, WGS-84 polygon area, haversine length, bounding box and an SVG preview.

File

Paste an IANA cipher suite name and get its key exchange, authentication, bulk cipher, mode and MAC — plus a security grade for forward secrecy and AEAD.

Network

Paste a PEM certificate and read it: subject, issuer, expiry, SANs, key, fingerprints and extensions — decoded in your browser.

Network

Paste any DER structure — PEM, base64 or hex — and see its ASN.1 tree: offsets, tags, lengths and decoded values.

Developer

Draw a random chess opening to study from 24 classical and modern lines, filtered by category, difficulty and side — with ECO codes and key moves.

Random

Compare seven different brightness metrics — HSL Lightness, HSV Value, WCAG Relative Luminance / LRV, CIE Lab L* perceived lightness, Rec.

Color & CSS

Detect edges in any image with the classic 3×3 gradient operators — Sobel, Scharr or Prewitt — with adjustable pre-blur, threshold and custom colors.

Image

Two-way converter between running pace (min/km, min/mile) and speed (km/h, mph, m/s), with race time projections from 5K to the marathon.

Convert

Compute the Equation of Time — the gap between mean and apparent solar time — for any date, plus your local solar noon and the sundial offset.

Time

Drop or paste any vCard 2.1, 3.0 or 4.0 .vcf export and read every contact as a card — names, phones, emails, addresses, photos and custom X- fields.

File

Build a mailto: URL with To, Cc, Bcc, subject, and body — RFC 6068 percent-encoded, ready to drop into an <a> tag.

Network

Randomly pair Secret Santa givers with recipients, with optional exclusion pairs and hidden reveal cards so the host never sees anyone's match.

Random

Apply all 16 W3C blend modes to two colors and see the computed hex for each, with a copyable mix-blend-mode CSS snippet per mode.

Color & CSS

Add a soft radial vignette to any photo — adjustable amount, softness, radius, oval / circle / rectangle shape, dark or light, any color.

Image

Convert any angle between degrees, radians, gradians, turns, milliradians, arcminutes, arcseconds and DMS, with a live SVG preview and π-fraction output.

Convert

Convert one moment in time between 11 epoch formats — Unix seconds and ms, NTP, Windows FILETIME, .NET Ticks, Mac HFS+, Excel serial, ISO 8601.

Time

Drop a .torrent or raw bencode file and inspect its tree, info hash (SHA-1), trackers, file list and piece length — parsed locally in your browser.

File

Decode CBOR (RFC 8949) from hex or base64 into readable diagnostic notation — including tags, floats and indefinite-length items. All in your browser.

Developer

Paste base64 or hex MessagePack bytes and read the values — types, nested maps, binary blobs and timestamps — decoded in your browser.

Developer

Paste base64 or hex protobuf bytes and read the fields — numbers, wire types, nested messages, strings and packed arrays — without a schema.

Developer

Coalesce a messy list of IPv4/IPv6 addresses, CIDR blocks, and ranges into the smallest equivalent set of CIDR prefixes.

Network

Generate a full round-robin pairing schedule where every participant meets every other participant exactly once — using the classic circle method.

Random

Compare how CSS color-mix() blends two colors across interpolation spaces (srgb, hsl, oklch, lab, lch, hwb) — live swatches and copyable CSS.

Color & CSS

Automatically crop empty transparent, white, black or solid-color borders off an image — with adjustable tolerance, padding and PNG/JPEG/WebP export.

Image

Score any English text on six classic readability formulas — Flesch Reading Ease, Flesch-Kincaid, Gunning Fog, SMOG, ARI and Coleman-Liau.

Text

Plot the classic biorhythm cycles — physical (23), emotional (28), intellectual (33 days) — with a ±15-day chart and a critical-day list.

Time

Drop a .har file from Chrome, Firefox or Safari DevTools and see every request — method, status, size, time — with slowest and largest tables.

File

Generate Certificate Authority Authorization (CAA) DNS records so only the CAs you trust can issue TLS certificates for your domain.

Network

Normalise, encode and check an SVCB or HTTPS record: SvcParams decoded, the wire bytes broken down, and every RFC 9460 rule it breaks named.

Network

Paste a list of participants and get a properly seeded single-elimination bracket — BYE handling, three seeding modes, and Markdown export.

Random

Visual builder for the CSS clip-path property — circle, ellipse, inset or polygon, with sliders, click-to-add points and 10 shape presets.

Color & CSS

Sharpen any photo or screenshot with the unsharp-mask algorithm — amount, radius and threshold sliders, four presets and a live before/after view.

Image

Count every character in your text — letters, digits, whitespace, punctuation — and compare against expected English frequencies for cryptanalysis.

Text

Generate printable mazes with adjustable size, cell scale, and reproducible seed — recursive-backtracking algorithm with optional solution overlay.

Random

How old are you on Mercury, Mars, Saturn or Pluto? Enter your birth date and see your age plus next-birthday countdown for every planet in the Solar System.

Time

Drop a .wav file and read its format, channels, sample rate, bit depth, duration, all RIFF chunks, and embedded LIST/INFO tags — fully client-side.

File

Open a .flac in your browser: STREAMINFO, every metadata block with its offset, repeated Vorbis comments, embedded art and the real compression ratio.

File

Walk an .ogg, .oga or .opus page by page: granule positions, segment tables, CRC32 checks, and the logical streams the container carries.

File

Read a compiled GNU gettext .mo catalogue in your browser: byte order, header, every msgid and translation, contexts, plural forms and untranslated strings.

File

Read a .gz header field by field, walk every member, and verify the trailer by recomputing CRC32 and the real size in your browser.

File

Read an .xz container: stream header, every block header and filter chain, the index and the footer — with the true uncompressed size, unpacking nothing.

File

Drop an MP3 and read its ID3 tags, bitrate and duration, and pull out the embedded cover art — all in your browser.

File

Open an Apple property list — binary or XML — and read it as a tree, or convert it to JSON or XML plist.

File

Stack as many text-shadow layers as you want — neon glow, 3D lift, outline, long shadow — live preview plus copy-ready CSS.

Color & CSS

Fake a miniature-diorama look on any photo — sharp focus band plus blurred top and bottom, with optional saturation boost, all in the browser.

Image

Write a template with {{placeholders}}, paste rows of data (CSV or JSON), and render one personalised text per row — entirely in your browser.

Text

Parse, compare, and bump semantic versions side-by-side, with a range expander that shows what ^x.y.z and ~x.y.z actually cover.

Developer

Convert any text into bionic reading format — first letters of each word bolded as fixation points to help your eyes glide faster through long passages.

Text

Net present value, every IRR, MIRR and payback for a list of cash flows — or XNPV and XIRR for dated ones — with the Excel NPV() trap shown.

Everyday

Compare two conversion rates: p-value, lift, Wilson and Newcombe intervals, a sample-ratio-mismatch check, and the sample size the next test needs.

Math & Statistics

Probabilities and quantiles for the normal, t, chi-square, F, exponential, binomial and Poisson distributions, accurate far into the tails.

Math & Statistics

One-sample, paired and two-sample t-tests from raw data or summary statistics: t, degrees of freedom, p-value, confidence interval and Cohen's d.

Math & Statistics

Rank-based tests for two independent samples or paired data: W or V, an exact or corrected p-value, rank-biserial r and the Hodges–Lehmann estimate.

Math & Statistics

Compare the means of several groups: one-way ANOVA, Welch's ANOVA, Kruskal–Wallis and Levene's test, with the ANOVA table and effect sizes.

Math & Statistics

Chi-square test of independence or goodness of fit: χ², df, p-value, expected counts, residuals, Cramér's V, and Fisher's exact test for 2 × 2 tables.

Math & Statistics

Pearson's r with a p-value and Fisher-z interval, Spearman's ρ and Kendall's τ-b from pasted pairs — with a warning when values and ranks disagree.

Math & Statistics

Paste (x, y) pairs and instantly get the best-fit line — slope, intercept, Pearson r, R², and a live prediction — all computed in your browser.

Math & Statistics

Generate live RFC 6238 TOTP codes from a Base32 secret — for testing 2FA flows, debugging authenticator integration, or a temporary fallback.

Developer