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How to Open RAR, 7z, and TAR Files in the Browser (No WinRAR Needed)

Extract .rar, .7z, .tar, .tar.gz, .tar.xz and 10+ other archive formats in the browser. libarchive.js runs the WinRAR / 7-Zip codebase as WebAssembly.

Extraction runs locally via Zro7 Extract Archive using libarchive.js (WASM). Archives never leave your device.

To open a RAR, 7z, or TAR file in the browser, drop it into Zro7 Extract Archive. libarchive.js — a WebAssembly port of libarchive, the same library behind macOS, GNOME, and KDE archive tools — reads the file locally and lets you extract everything or just a few entries. No WinRAR install, no signup, no upload.

Formats supported

  • RAR (v3, v4, v5) — including solid archives.
  • 7z — LZMA, LZMA2, BZIP2, DEFLATE, PPMd streams.
  • TAR and TAR-based: .tar.gz, .tgz, .tar.bz2, .tar.xz, .tar.zst.
  • ZIP, ISO, CAB, CPIO, AR, LHA/LZH, XAR.
  • Password-protected ZIP and RAR entries — prompt appears on demand.

Why WASM libarchive beats WinRAR here

WinRAR ($29 shareware) and 7-Zip (Windows only, GUI) both require installs and admin permission. libarchive.js is the same C codebase compiled to WASM: it runs in Chrome, Safari, Edge, or Firefox on macOS, Windows, Linux, Chromebook, iPad, and Android — with zero install. Cloud extractors (e.g. Unzip-Online, Ezyzip's server tier, Archive Extractor) upload your file first, which is the exact scenario a signed / encrypted archive is trying to avoid.

Steps

  1. Open Extract Archive.
  2. Drop a .rar, .7z, .tar.gz (etc). The entry list renders.
  3. Select entries to extract, or click Extract all — files download individually or as a fresh ZIP.

Frequently asked questions

Are solid RARs supported?

Yes. libarchive handles both non-solid and solid RAR v3/v4/v5 archives.

What about encrypted 7z archives?

AES-256 encrypted 7z entries prompt for the password, then decrypt in-browser.

Multi-part RARs (.r00, .r01)?

Supported — drop all parts together and libarchive reassembles the stream.

Any size limit?

Bounded by browser memory. Multi-GB archives work on desktop; mobile Safari caps sooner.

Any upload?

None. libarchive.js is pure WASM running in your tab.

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