What is 7z (7-Zip archive)?
7z is the archive format of 7-Zip and compresses very strongly with LZMA2, at the cost of needing extra software.
A 7z file you received will not open? Converting 7z to ZIP gives a file every computer and phone understands. This tool reads 7z but does not create it.
File extensions: .7zMIME types: application/x-7z-compressed
Advantages
- Very high compression
- Strong AES-256 encryption
- Open format, free tools
Disadvantages
- Needs 7-Zip or a similar app on most systems
- Slow to pack at high settings
- Phones rarely open it
Typical uses
- Large downloads and mod packs
- Long-term archives
- Sending big folders as small as possible
Compatibility
Windows 11 opens it in Explorer, otherwise 7-Zip, Keka (macOS) or p7zip (Linux) are needed; most phones need an app.
Convert 7Z to another format
Frequently asked questions
Are my files uploaded to a server?
No. The conversion runs entirely in your browser with local code. Your files never leave your device, and there is no upload.
Is there a file size limit?
There is no limit on our side, but your browser memory is. Images work for very large files; for videos, files above a few hundred megabytes can fail on devices with little memory.
Will the quality suffer?
That depends on the target format and settings. Use the quality option to balance size and detail; lossless targets keep everything the source contained.
Which browsers are supported?
Current versions of Chrome, Edge, Firefox and Safari. Fast hardware paths are used where available, with a compatible fallback otherwise.