.7z

What is a .7z file?

7Z is a high-compression archive format that uses the LZMA2 algorithm to produce noticeably smaller files than ZIP or RAR.

Use caution
Type Archive
By Igor Pavlov
MIME application/x-7z-compressed

Drop any file to identify it

We read file headers, not extensions. Nothing gets uploaded.

What is it

7Z is a high-compression archive format that uses the LZMA2 algorithm to produce noticeably smaller files than ZIP or RAR. The compression nerd's choice. The trade-off is convenience: Windows and macOS cannot open 7Z files natively, so anyone you send one to needs 7-Zip, PeaZip, or The Unarchiver. It also supports AES-256 encryption and solid compression (treating multiple files as a single data stream for better ratios). Power users love it. Everyone else just uses ZIP.

Technical details
Full Name
7-Zip Archive
MIME Type
application/x-7z-compressed
Developer
Igor Pavlov
Magic Bytes
37 7A BC AF 27 1C
Safety
.7z requires caution. Archive files from unknown sources may contain malware. Scan contents before extracting.
What opens it
7-Zip
FREE Windows
The Unarchiver
FREE macOS
PeaZip
FREE All
FAQ
What's the difference between 7Z and ZIP?
7Z compresses smaller (often 10-30% better) but is not natively supported by Windows or macOS. ZIP works everywhere without extra software. Use ZIP for sharing, 7Z for archiving when size matters.
How do I open a 7Z file?
On Windows, install 7-Zip (free). On macOS, use The Unarchiver (free, from the App Store). On Linux, most file managers handle 7Z out of the box.
Is 7Z safe?
The format itself is safe. Like any archive, the contents could be malicious — scan extracted files with antivirus. The encryption (AES-256) is actually stronger than ZIP's built-in encryption.
Related formats