Convert GZ to ZIP online
Drop a .gz and download a .zip containing the decompressed file — handled entirely in your browser, no command line, no upload.
Drop your .gz anywhere on this page
The gz is decompressed and re-packed as a ZIP in your browser — nothing is uploaded.
A .gz is gzip — a stream compressor that squeezes exactly one file. It is not a multi-file archive: data.csv.gz decompresses to data.csv, and that is the whole relationship. (Bundles like project.tar.gz are a tar *inside* the gzip — that is a different conversion, covered under tar.gz to ZIP.) Converting a .gz to a .zip means decompressing that one file and wrapping it in the universal container, so recipients get the original file inside a .zip that opens anywhere.
ZipTool does it in your browser. You open the page, drop the .gz onto it, and the file inside renders locally — the gzip layer uses the browser's own decompression support, with no decoder to download. Click Convert in the file-tree toolbar, pick ZIP, and download the rebuilt archive. Nothing is uploaded; the network is only ever used to load the page itself. For the format background, see the gz format page.
How to convert GZ to ZIP in your browser
No command line, no upload. The browser decodes the .gz and writes the .zip locally.
- Go to ZipTool and drag the
.gzonto the page (or use the file picker, or paste a URL). The archive is decoded in your browser and the file tree opens. - Click Convert in the file-tree toolbar (next to Extract-all). The converter reads the GZ entries that are already in memory.
- Choose ZIP as the output format. The entries are re-packed into a standard
.zipwith Deflate compression and a central directory - Download the
.zip. The rebuilt archive is produced locally and handed to you as a download — your original GZ and its contents are never transmitted anywhere.
Is it really private?
Yes. "Online" here describes where the tool runs — a web page — not where your data goes. The .gz is decoded by the browser's built-in gzip decompression running inside your tab, the entries are re-packed into a ZIP in memory, and the result is offered as a download. No server ever receives your file, its contents, or the converted archive.
You can prove it to yourself in a few seconds. Drop a .gz onto the page, wait for the file tree to open, then disconnect from the internet. The convert-to-ZIP step still works, because nothing about it depends on a network request. A tool that fails the moment you go offline was uploading your data. ZipTool does not. For the broader privacy case, see why client-side is safer than uploading.
Why convert GZ to ZIP?
The motivation is almost always the recipient's operating system. macOS and Linux open a .gz natively, but on Windows — outside recent Windows 11 releases — a .gz typically lands as an unknown file type until someone installs 7-Zip or WinRAR. A .zip sidesteps the question: it has opened with a double-click since Windows XP. Emailing a gzipped log or dataset to a Windows user is the classic case for converting first.
One expectation to set: the resulting .zip will be about the size of the original .gz. The data was already compressed, and ZIP re-applies its own Deflate to the decompressed file — landing near the same size, just in a friendlier container. If your goal is many files in one archive, a gz cannot do that; you want a tar.gz, or a zip built with create a zip online. To decompress a gz without the zip step, see the gz format page.
Honest limits
Conversion is a real capability here, with a few real boundaries worth knowing.
- You cannot convert TO RAR or 7Z. RAR encoding is proprietary to WinRAR — no browser (and no honest free tool) can *create* a
.rar. ZipTool converts in the other direction only: RAR, 7z, tar.gz, tar, and gz *into* ZIP, TAR, or TAR.GZ. See creating a zip online. - A .gz holds exactly one file. Gzip is a stream compressor, not an archive — the resulting ZIP contains the single decompressed file and nothing else. Bundling many files is tar.gz's job, not gzip's.
- Browser memory is the ceiling. The tab holds the decoded entries and the rebuilt ZIP in memory, so a very large
.gzcan get slow. For multi-gigabyte archives a desktop tool is more reliable.
Frequently asked questions
How do I convert a gz to a ZIP online?
Open the page and drop your .gz onto it. The file inside is decompressed in your browser, and you click Convert in the toolbar, choose ZIP, and download a .zip containing the decompressed file. No command line, no install, no upload.
Can a .gz contain multiple files?
No. Gzip compresses exactly one stream — one file. An archive holding many gzipped files (like a .tar.gz) is really a tar bundle passed through gzip. If you have several files to package, you need a zip or a tar.gz, not a gz.
Why is the ZIP about the same size as my gz?
Because the data was already compressed. Converting decompresses the file and re-compresses it with ZIP's Deflate — a sibling algorithm of gzip — so it lands within a few percent of the original. The win is compatibility, not size.
Do you upload my gz to convert it?
No. The file is decompressed by the browser itself and re-packed into a ZIP in memory; the result is downloaded locally. This conversion has no decoder download at all — your file never leaves the tab. Confirm it in DevTools (the Network tab shows no upload) and by converting with the internet disconnected, which still works.
Is converting gz to ZIP free?
Yes. Decompressing the gz and re-packing it as a ZIP is completely free, with no account and no install. Everything runs locally in your browser; there is no per-file paywall.