About extract7z

extract7z is a free, private, browser-based archive tool. It opens 7Z, ZIP, RAR, TAR, GZ, BZ2, XZ, CAB, ISO and other common archive formats — and builds encrypted ZIPs — entirely in your browser.

//How it works

The site is a static collection of HTML, CSS and JavaScript. There is no backend. When you open an archive, the file is loaded into your browser's memory and processed by:

• libarchive.js — a WebAssembly build of libarchive, the C library that powers many native archive tools. It handles 7Z, RAR, TAR and most other formats.
• zip.js — a fast modern ZIP library used for output, including AES-256 encryption.

You can verify the privacy claim yourself: load this site, then disconnect from the internet. Every tool still works — nothing depends on a server round-trip.

//Why we built it

Most online “extract a file” tools upload your archive to their server, queue it, decompress it, then offer a download. That has three problems: it's slow (upload + download), it's a privacy risk (your files sit on someone else's server), and it imposes file-size limits.

Modern browsers can do everything client-side. WebAssembly delivers near-native speed for compression algorithms; the File API gives JavaScript direct access to local files. There's no good reason to ship your files to anyone.

//Open-source libraries used

• libarchive.js (BSD license)
• zip.js (BSD-3-Clause license)

This site is funded by unobtrusive ads via Google AdSense. If you find it useful, just bookmark it and share it — that's the whole business model.