RAR to Z Converter
FileFlip converts RAR to Z entirely inside your browser, using libarchive compiled to WebAssembly. The file is never uploaded to a server: it is read off your disk, converted on your own machine, and saved back by the browser. That means no file-size limit, no queue and no account.
How do I convert a RAR file to Z?#
- Drop your RAR file onto the converter at the top of this page, or click it to pick one from your computer. You can add as many as you like.
- Leave the target set to Z and the conversion starts on its own. FileFlip downloads 1.0 MB of WebAssembly the first time and nothing after that, then runs libarchive on your own machine.
- Save the Z file. Your browser writes it straight to your downloads folder, because there was never a server holding it.
Does converting RAR to Z lose quality?#
No. Converting RAR to Z does not touch the files inside the archive. Each member is read out and written back byte for byte, so only the wrapper around them changes and nothing is recompressed.
Is it safe to convert RAR files online?#
Yes, because nothing is uploaded. FileFlip converts RAR files inside the browser tab you already have open, using WebAssembly builds of the same engines a desktop converter would install. Your file is read from your own disk into the page's memory, and no request carrying it is ever made.
You do not have to take that on trust. Open your browser's network panel, run a conversion, and you will see the engine come down and your file go nowhere. There is no upload, no server-side copy, no retention window, and no account tied to what you converted.
How FileFlip works lists every engine, its version and its download size, and shows how to check for yourself that nothing leaves your machine.
What RAR to Z actually does to the file#
Converting RAR to Z runs on libarchive, downloads 1.0 MB of WebAssembly the first time and nothing after that, copies the archived files through unchanged, keeps file contents.
| Engine | libarchive |
|---|---|
| Conversion path | 2 steps: RAR → the unpacked files → Z |
| Downloaded to your browser | 1.0 MB, once, then cached by your browser |
| Quality | Lossless, contents copied unchanged |
| You get back | One file |
| Where it runs | In a background worker, so the page stays responsive |
What survives the conversion
| What is in the file | This conversion | Why |
|---|---|---|
| File contents | Kept | Carried through into the converted file. |
| File timestamps | Sometimes | Survives for some files and not others. |
| File permissions | Sometimes | Survives for some files and not others. |
Worth knowing before you start:
- the output is a PAX tar archive inside the compressor, not a single compressed stream
- every entry is extracted into memory before anything is written, so a very large archive can exhaust it
- no passphrase is passed to the reader, so an encrypted archive cannot be opened
What is a RAR file?#
A RAR file holds data compressed with RARLAB's proprietary algorithm, which since RAR5 in 2013 has combined LZSS-style matching with a PPMd model and can span a single archive across multiple numbered volumes.
Use RAR when an archive needs to be split across multiple size-capped volumes or carry a recovery record that can survive some file damage.
Convert RAR to ZIP or 7z when the archive needs to be rebuilt or edited, since nothing free can write a new RAR file, only read one.
What is a Z file?#
A Z file is a single stream compressed with the LZW algorithm by the Unix compress utility, the format gzip was written specifically to replace once a patent on LZW made distributing compress a legal risk.
There's essentially no reason to create a new Z file today; gzip replaced it decades ago with better compression and no patent risk.
Convert an old Z file to GZ or XZ so modern tools that dropped compress support can actually open it.
RAR to Z questions people ask#
Why can I only extract RAR files but not create them for free?
RAR is Eugene Roshal's proprietary format, and RARLAB only licenses the compressor, sold as WinRAR or the rar command-line tool, while distributing the unrar decompression source freely under a license that explicitly forbids using it to build a compatible archiver. That's why free tools like 7-Zip and The Unarchiver can open RAR files but none of them can write one.
Why is a RAR split into .part1.rar, .part2.rar files?
That's RAR's native multi-volume support, which splits one archive across several numbered files so it fits somewhere with a size limit, like an email attachment cap. All the parts have to be present to extract the contents.
What's the difference between RAR4 and RAR5?
RAR5, introduced in 2013, raised the maximum dictionary size to 1 GB, switched to 256-bit AES encryption and BLAKE2 hashing, added UTF-8 filename support, and improved multicore decompression speed over the older RAR4 format. Current WinRAR still reads and writes both.
What is a RAR recovery record?
A recovery record is optional redundant data a RAR archive can store alongside the compressed files, which lets tools reconstruct part of the archive if it gets corrupted or truncated later. It has to be added when the archive is created; a RAR without one can't be repaired after the fact.