Archive Format Guide: ZIP, TAR, 7z, and RAR Compared
Compare archive formats for compression ratio, speed, encryption, and cross-platform compatibility. Understand the difference between archiving and compression, and when each format excels.
Key Takeaways
- Archiving bundles multiple files into one container.
- ZIP: Universal interchange — every OS opens ZIP without extra software.
- ZIP's legacy encryption (ZipCrypto) is trivially broken — always use AES-256 when encrypting ZIP archives.
- ## Encryption Warnings ZIP's legacy encryption (ZipCrypto) is trivially broken — always use AES-256 when encrypting ZIP archives.
Archiving vs Compression
Archiving bundles multiple files into one container. Compression reduces file size. Some formats do both (ZIP, 7z), while TAR is archive-only — it is typically combined with a separate compressor (gzip → .tar.gz, bzip2 → .tar.bz2, zstd → .tar.zst). Understanding this distinction explains why TAR+GZIP often compresses better than ZIP — it can find redundancy across files.
Format Comparison
| Format | Compression | Speed | Encryption | Cross-Platform |
|---|---|---|---|---|
| ZIP | Medium | Fast | AES-256 (optional) | Universal |
| TAR.GZ | Medium | Fast | Via GPG only | Unix native |
| TAR.ZST | High | Very fast | Via GPG only | Growing |
| 7z | Very high | Slow | AES-256 | Requires 7-Zip |
| RAR | High | Medium | AES-256 | Requires WinRAR |
When to Use Each
ZIP: Universal interchange — every OS opens ZIP without extra software. Use for files shared with non-technical users.
TAR.GZ: Unix/Linux standard. Use for code archives, backups, and deployment packages. Preserves Unix permissions and symlinks.
7z: Maximum compression ratio. Use when file size matters more than speed or universal compatibility.
TAR.ZST: Modern alternative to TAR.GZ with better compression at higher speed. Gaining adoption in Linux distributions.
Encryption Warnings
ZIP's legacy encryption (ZipCrypto) is trivially broken — always use AES-256 when encrypting ZIP archives. RAR and 7z encryption is strong by default. For TAR archives, encrypt the entire archive with GPG rather than relying on the archiver.