ZIP Converter
FileFlip converts ZIP files into 10 other formats entirely inside your browser, using libarchive compiled to WebAssembly. The ZIP file is never uploaded to a server: it is read off your disk, converted on your own machine, and saved back by the browser. There is no file-size limit and no account to create.
How do I convert a ZIP file?#
- Drop your ZIP file onto the converter at the top of this page, or click it to pick one from your computer.
- Choose the format you want out of it. FileFlip downloads the engine that conversion needs, once, and your browser caches it.
- Conversion starts the moment you pick the format, and the result is yours to download. The work happens in this tab, so nothing is uploaded and nothing is queued.
Is it safe to convert ZIP files online?#
Yes, because nothing is uploaded. FileFlip converts ZIP 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 happens to a ZIP file#
FileFlip converts ZIP into 10 formats with libarchive, all of it inside the browser tab. Each conversion below names the engine it uses, what it downloads, and exactly what that conversion keeps or drops.
| Category | Archives |
|---|---|
| File extension | .zip |
| FileFlip support | Read and written |
| Conversions available | 10 |
| Engines | libarchive |
| Downloaded to your browser | 1.0 MB on the first conversion, then cached |
What is a ZIP file?#
A ZIP file is a container introduced by PKWARE in 1989 that holds any number of files and folders, each one compressed and stored as its own separate entry alongside a central directory listing them.
Use ZIP when the archive has to open on any device without the recipient installing anything, or when individual files need to be pulled out rather than the whole archive at once.
Convert away from ZIP when the same files need to be smaller for storage or transfer, since 7z or xz's solid compression usually beats it at the cost of that per-file random access.
The ZIP file format reference covers the specification, the programs that open one, and what each conversion keeps or drops.
ZIP questions people ask#
Why can I open one file from a ZIP without extracting the whole thing?
A ZIP archive compresses each file inside it separately and lists them in a central directory at the end, so a tool can jump straight to one entry and decompress only that file. Formats like TAR.GZ compress everything as one continuous stream and don't have this shortcut.
Is a ZIP password actually secure?
It depends which encryption the ZIP uses. The original ZipCrypto method is weak enough to crack in seconds with widely available tools; only the newer AES-256 option, which not every zip program offers, is actually secure.
Why won't some old programs open a large ZIP file?
The original 1989 ZIP specification capped archives at 4 GiB and 65,535 files, and a tool that doesn't implement the ZIP64 extension added in 2001 fails on anything past that. Nearly every modern zip tool supports ZIP64, so this mostly comes up with older software.
What's the difference between ZIP and 7z?
ZIP compresses each file separately, which makes extracting a single item fast; 7z compresses the whole archive as one solid LZMA2 stream, which usually produces a smaller file but has to decompress more to reach an item near the end. 7z also isn't opened natively by Windows or macOS the way ZIP is.
Can a ZIP file contain other ZIP files?
Yes, a ZIP archive treats a nested .zip the same as any other file and stores it as an already-compressed entry, though compressing it again rarely shrinks it further since the inner archive's data is already dense.