Both are 128 bits of randomness, but ULID's first 48 bits encode the timestamp — IDs generated later sort after earlier ones, useful for DB primary keys.

Why NanoID instead of UUID?

Shorter (21 chars vs 36), URL-safe by default, and the alphabet is configurable. Same crypto strength as UUIDv4 at default size.

Yes — uses crypto-secure RNG and a configurable length. Designed specifically to be hard to guess (no embedded timestamp or fingerprint to leak).

Are these RFC-compliant?

ULID has a community spec. NanoID and CUID2 are de-facto standards with reference implementations. None are RFC-numbered like UUID.

ULID / NanoID / CUID2 Generator

Three modern ID schemes for distributed systems. **ULID** is 26 chars, lexicographically sortable by time, encodes ms timestamp + 80 random bits. **NanoID** is a customizable-alphabet random ID — same security as UUIDv4 but shorter and URL-safe. **CUID2** is collision-resistant, fingerprint-free, secure by default. All are generated with `crypto.getRandomValues` and rejection sampling for uniform distribution.

—

Count

About

ULID: 26 chars · 48-bit timestamp + 80-bit random · Crockford Base32 · sortable by time.

How to use

Pick a scheme (ULID, NanoID, CUID2).
For NanoID/CUID2, choose ID length; for NanoID, optionally edit alphabet.
Set count and generate. Copy individual IDs or all at once.

Frequently asked questions

ULID vs UUIDv4?: Both are 128 bits of randomness, but ULID's first 48 bits encode the timestamp — IDs generated later sort after earlier ones, useful for DB primary keys.
Why NanoID instead of UUID?: Shorter (21 chars vs 36), URL-safe by default, and the alphabet is configurable. Same crypto strength as UUIDv4 at default size.
Is CUID2 secure?: Yes — uses crypto-secure RNG and a configurable length. Designed specifically to be hard to guess (no embedded timestamp or fingerprint to leak).
Are these RFC-compliant?: ULID has a community spec. NanoID and CUID2 are de-facto standards with reference implementations. None are RFC-numbered like UUID.

Guides on this topic

Choosing an ID Format: UUID, ULID, Snowflake or Auto-increment A practical guide to picking identifiers — auto-increment integers, UUID v4/v7, ULID and Snowflake IDs — and the trade-offs in uniqueness, ordering, size and privacy.

Related tools

UUID Generator

Generate random version-4 UUIDs in bulk, with copy.

Developer 0 0

ULID Decoder (Timestamp & Randomness)

Decode a ULID into its 48-bit creation timestamp and 80-bit randomness — Crockford Base32, case-insensitive, with the time as ISO UTC, relative, and epoch milliseconds — entirely in your browser.

Developer 0 0

Snowflake ID Decoder (Discord, Twitter)

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

Developer 0 0

Hash Generator (SHA)

Generate SHA-1, SHA-256, SHA-384, and SHA-512 hashes from text.

Developer 0 0

JSON → TypeScript Interface

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

Developer 0 0

JSON to JSDoc @typedef Generator

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

Developer 0 0