How to Open RAR Files Online — No WinRAR Required

RAR is a proprietary format created by Eugene Roshal (the "R" in "RAR" stands for his name). Unlike ZIP — which is built into Windows, macOS, and Linux — RAR requires third-party software to open. No operating system ships with native RAR support as of 2026.

This is by design: the RAR format is owned by win.rar GmbH, the company that makes WinRAR. While they allow RAR files to be read freely by third-party tools, creating RAR files requires a licence.

The good news: you don't need WinRAR to read RAR files. Several free tools — including browser-based ones — can open them without any installation.

There are two major versions of the RAR format that you'll encounter:

RAR4 (classic RAR): The format used by WinRAR before version 5.0 (released 2013). Widely supported by almost all archive tools.

RAR5: The modern RAR format. Uses a larger compression dictionary for better compression ratios, AES-256 encryption instead of RAR4's weaker encryption, and a different internal structure. Some older tools only support RAR4.

FastZip.io supports both RAR4 and RAR5 — you can open either version without knowing which one your file is.

Opening a RAR with FastZip.io takes four steps:

Step 1: Go to the RAR Extractor tool. No account or sign-up required. The tool is free for files up to 200 MB.

Step 2: Drop your RAR file onto the page (or click to browse your files). The file stays on your device — nothing is uploaded.

Step 3: Wait for processing. The WASM engine reads the RAR archive and shows you a list of all files inside. For a 100 MB archive on a modern laptop this takes 2–5 seconds.

Step 4: Download what you need. Extract all files at once as a ZIP, or click individual files to download just what you need.

The whole process is private: your RAR file never leaves your device at any point.

Multi-part RARs split a large archive across several files, usually named something like:

• file.part1.rar, file.part2.rar, file.part3.rar (modern naming) • file.rar, file.r00, file.r01, file.r02 (classic naming)

To open a multi-part RAR, you need all parts. FastZip.io currently supports multi-part RAR extraction by selecting all parts at once in the file browser. The tool automatically assembles them in the correct order.

Note: if any part is missing, the archive cannot be fully extracted — this is by design. The parts are not independent archives, they are segments of one continuous archive.

If your RAR file is password-protected, you'll be prompted to enter the password after dropping the file. FastZip.io uses the password locally to decrypt the archive — the password is never sent to any server.

If you don't have the password, there is no way to recover it. AES-256 encryption (used by RAR5) is not crackable by any realistic means. If you received the file from someone, ask them for the password — there is no backdoor.

Note: RAR4 used an older, weaker encryption scheme. Specialised recovery tools exist for RAR4-encrypted archives, but they are slow and require a known or guessable password to work. FastZip.io does not include password recovery functionality.

Use a browser tool when: • You occasionally receive RAR files and don't want software cluttering your computer. • You're on a managed work or school device where you can't install software. • You're on a phone or tablet. • You need to share just a few files from a RAR without extracting everything.

Use a desktop tool (7-Zip, PeaZip, The Unarchiver) when: • You regularly work with large archives (2 GB+). • You need to create RAR files (browser tools can only read RAR, not create it). • You need advanced features like repair, recovery records, or solid archives.

For the vast majority of "I just received a RAR and need to open it" situations, a browser tool is faster and simpler than installing desktop software.