Files with the .7Z extension contain compressed data archives, by default using LZMA compression, with an open source code, also supporting 256-bit AES encryption. The format also supports compression using the PPMD, BCJ, BCJ2, BZip2, and Deflate methods. It allows for naming Unicode files and compression of archive headlines – the maximum file size is 1,6·1010 GB.

7Z files are created by the archiving program 7-Zip, created by Igor Pavlov and available for free on the 7-zip.org website.