I was working with a file, for a previous post, through which I had a large file to upload. I’ve used 7-Zip for a while, but this is the first time I’ve really noticed differences against a Zip file.
Below is a chart of my findings (each using the highest available compression format):
| Format | Size | Compression ratio of Original |
| Original file | 58,412 KB | – |
| .7z | 3,173 KB | 5.4% |
| .Zip | 25,490 KB | 43.6% |
| .bz2 | 21,875 KB | 37.4% |
| .gzip | 25,459 KB | 43.5% |
| Windows Compressed Folder | 27,247 KB | 46.6% |
As you can see, using the .7z format gives a substantial improvement in compression over any of the other formats.
I hereby highly recommend 7-zip! 
Disclaimer: Results will vary with different content! !
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