A free, open-source file archiver, in a single file, for your thumb drive, hard drive, CD, etc. No installation required!

7-Zip is a file archiver with a high compression ratio for ZIP and GZIP formats, which is between 2 to 10% better than its peers, depending on the exact data tested. And 7-Zip boosts its very own 7z archive format that also offers a significantly higher compression ratio than its peers—up to 40% higher! This is mainly because 7-Zip uses LZMA and LZMA2 compression, with strong compression settings and dictionary sizes, to slow but vastly improve density. If a zip tool gains its appeal from its ability to efficiently compress files, then 7-Zip proves it has a little bit o’ magic.