7Z is an open format with no licensing restrictions. RAR requires WinRAR to create archives. 7Z can be created and opened with the free 7-Zip tool.
No. The conversion only repackages the contents. The files inside remain unchanged.
7Z generally achieves slightly better compression than RAR, especially for large files.
Yes. The free Keka app on macOS supports 7Z files. The Archive Utility built into macOS does not support 7Z.
Yes. 7Z supports AES-256 encryption for both file content and filenames.
Yes. Install p7zip on Linux: sudo apt install p7zip-full. Then use the 7z command to extract files.
7Z can achieve compression ratios of 2:1 to 10:1 depending on the file type. Text files compress much better than already-compressed files like JPG or MP4.