Nothing is uploaded. When you drop or pick a .rar, the tool reads it locally with the browser’s File API, parses the RAR4 or RAR5 headers in memory to list the contents, and — when you click Extract — decompresses the data with a WebAssembly build of the libarchive library that runs inside the page. There is no server, API, database or tracking in the processing path, so confidential documents, source code or personal files stay on your machine; the tool works offline once cached, and closing the tab discards everything. If an archive is encrypted, the password you type is used only by the local WASM engine and is never transmitted. The only optional network use anywhere on the site is consent-gated advertising, which never sees your data.

The tool flags encryption the moment it parses the headers, marking encrypted entries with a lock icon and showing how many files are protected. When you extract, it asks for the password and hands it to the local libarchive WebAssembly engine, which performs the AES-128 (RAR4) or AES-256 (RAR5) decryption in the browser. Because the whole operation is client-side, the password is only ever held in memory on your device and is never sent to any server. If the password is wrong or a particular entry cannot be decrypted, the tool reports it so you can try again rather than silently producing corrupt files.

Windows and macOS have no built-in RAR support, which is why opening a .rar usually means installing desktop archive software, 7-Zip or The Unarchiver first. This extractor replaces that with a web page: the RAR4 and RAR5 header parsers are written in JavaScript and the decompression is handled by a WebAssembly port of libarchive, so everything you need arrives with the page. There is nothing to install, no account and no platform lock-in — it works the same on Windows, macOS, Linux, Chromebooks and mobile browsers, and it keeps working offline once the page has been cached.

RAR4 (also called RAR 2.9) is the long-standing format produced by older desktop archive software versions; it uses AES-128 for encrypted archives and a fixed-layout header keyed by an ASCII “Rar!” marker and a seven-byte signature. RAR5, introduced in desktop archive software 5, is the current format: it has an eight-byte signature, a completely redesigned header structure based on variable-length integers, stronger AES-256 encryption and better recovery records. This tool detects the format automatically from the signature and reads either one, listing every entry with its sizes, timestamps and flags, and it can decompress both through the libarchive WebAssembly engine. It also recognises solid archives, where files share a single compression stream, and multi-volume (split) archives.