No. fflate unpacks the archive in memory inside your browser — the ZIP and its contents never leave your device.

Which ZIPs are supported?

Standard ZIP archives compressed with the Deflate algorithm (what most tools produce). Encrypted ZIPs and Zip64-only archives may not open.

Why are some files shown as 'binary'?

The preview decodes as UTF-8 text. If the first bytes contain many non-printable characters, the file is treated as binary and the preview is skipped — but you can still download it.

How big a ZIP can I open?

Limited by your browser's available memory. Hundreds of MB usually works; multi-gigabyte archives may be slow or fail to load.

ZIP Inspector

Drag in a ZIP archive and instantly see the file tree, individual sizes, and total uncompressed size. Click any text file (source code, JSON, configs) for an inline preview, or download a single entry without extracting the whole archive. Powered by fflate, runs entirely in your browser — no upload, no temp files on disk.

—

Drop a ZIP hereor click to choose

How to use

Drop a .zip file or click to choose one.
Browse the entries; click any file name to preview.
Use the per-row Download button to save a single file.

Frequently asked questions

Is the ZIP uploaded?: No. fflate unpacks the archive in memory inside your browser — the ZIP and its contents never leave your device.
Which ZIPs are supported?: Standard ZIP archives compressed with the Deflate algorithm (what most tools produce). Encrypted ZIPs and Zip64-only archives may not open.
Why are some files shown as 'binary'?: The preview decodes as UTF-8 text. If the first bytes contain many non-printable characters, the file is treated as binary and the preview is skipped — but you can still download it.
How big a ZIP can I open?: Limited by your browser's available memory. Hundreds of MB usually works; multi-gigabyte archives may be slow or fail to load.

Related tools

HAR File Inspector (HTTP Archive Viewer)

Drop a .har file from Chrome / Firefox / Safari DevTools and instantly see every request — method, status, size, time, content type — with stats, slowest/largest tables, and filterable / sortable entries. Runs entirely in your browser.

File 0 0

ZIP Builder

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

File 0 0

EML File Viewer

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 0 0

Bulk File Renamer Preview

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

File 0 0

Audio Trimmer

Cut a clip out of an audio file by dragging across its waveform, add fades, and download it as a WAV. Nothing is uploaded.

File 0 0

File Encoding Detector

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 0 0