Why no 7-Zip support?

The smallest working in-browser 7z library is a ~1.5 MB WebAssembly build under LGPL, which we can use but would need to disclose. For v1 we'd rather ship without it and add it later if traffic warrants — most archives in the wild are ZIP or RAR, and 7z extraction has good native support in every OS.

Why can I extract RAR but not create it?

The RAR format is proprietary. WinRAR licenses the decompressor freely (used by node-unrar-js) but not the compressor — there is no open-source RAR writer, anywhere. ZIP and TAR are free and unencumbered, so use one of those for new archives.

Are large archives handled well?

We load and process the entire archive in memory using fflate, which is fast but caps practically at around 1 GB depending on your browser. For multi-GB tarballs, use a desktop tool. (We may add streaming extraction later if traffic justifies the complexity.)

What's the difference between TAR.GZ and ZIP?

Both are containers with compression. ZIP compresses each file independently and stores a directory at the end (random-access friendly). TAR.GZ wraps every file in a TAR archive then gzips the whole thing as one stream — usually a little smaller for many small files, but you must decompress the whole thing to read any one entry. Unix tooling defaults to TAR.GZ; Windows defaults to ZIP.

Is any of this uploaded?

No. fflate is pure JavaScript, RAR extraction uses a WebAssembly build of unrar that runs locally. Open the network tab while you create or extract — nothing leaves your device.

tools / archive

Archive tools.

Create ZIP, TAR, TAR.GZ or GZIP archives, or extract any of those plus RAR — entirely in your browser. Files never touch a server.

Bundle multiple files into a ZIP, TAR or TAR.GZ — or wrap a single file as GZIP. Done locally, no upload.

Drop files to archive

● Stays on your device. Nothing is uploaded.

Order doesn't matter for ZIP/TAR. GZIP wraps one file only — use TAR.GZ for many.

FAQ

Why no 7-Zip support?: The smallest working in-browser 7z library is a ~1.5 MB WebAssembly build under LGPL, which we can use but would need to disclose. For v1 we'd rather ship without it and add it later if traffic warrants — most archives in the wild are ZIP or RAR, and 7z extraction has good native support in every OS.
Why can I extract RAR but not create it?: The RAR format is proprietary. WinRAR licenses the decompressor freely (used by node-unrar-js) but not the compressor — there is no open-source RAR writer, anywhere. ZIP and TAR are free and unencumbered, so use one of those for new archives.
Are large archives handled well?: We load and process the entire archive in memory using fflate, which is fast but caps practically at around 1 GB depending on your browser. For multi-GB tarballs, use a desktop tool. (We may add streaming extraction later if traffic justifies the complexity.)
What's the difference between TAR.GZ and ZIP?: Both are containers with compression. ZIP compresses each file independently and stores a directory at the end (random-access friendly). TAR.GZ wraps every file in a TAR archive then gzips the whole thing as one stream — usually a little smaller for many small files, but you must decompress the whole thing to read any one entry. Unix tooling defaults to TAR.GZ; Windows defaults to ZIP.
Is any of this uploaded?: No. fflate is pure JavaScript, RAR extraction uses a WebAssembly build of unrar that runs locally. Open the network tab while you create or extract — nothing leaves your device.