7Z vs LZ4
A detailed comparison of 7-Zip Archive and LZ4 Compressed — file size, quality, compatibility, and which format to choose for your workflow.
7-Zip Archive
Archives & Compressed7z uses the LZMA2 compression algorithm to achieve significantly better compression ratios than ZIP. It is open-source and supports strong AES-256 encryption.
About 7Z filesLZ4 Compressed
Archives & CompressedLZ4 is an extremely fast lossless compression algorithm focused on speed over compression ratio. It can compress at over 500 MB/s per core and decompress at multiple GB/s, making it the standard choice for real-time and in-memory compression.
About LZ4 filesStrengths Comparison
7Z Strengths
- Outstanding compression ratio — typically 20–50% smaller than ZIP, 10–30% smaller than RAR.
- Completely free and open source.
- AES-256 encryption of both content and filenames.
- Supports enormous archives (16 exabytes).
- Multi-threaded compression on modern CPUs.
LZ4 Strengths
- Decompression speed — approaches memcpy throughput.
- Very fast compression — can keep up with SSD write speeds.
- Stable format — reference implementation unchanged for years.
- Widely deployed in databases, filesystems, and kernels.
- BSD-licensed library.
Limitations
7Z Limitations
- Not natively supported on Windows before Windows 11 23H2 or macOS — requires a separate tool.
- Slower compression than ZIP (though decompression is fast).
- No built-in recovery records like RAR.
- Less ubiquitous in email and casual sharing than ZIP.
LZ4 Limitations
- Compression ratio lags gzip by 20-30%.
- Not designed for long-term archival where ratio matters.
- Older than zstd, which beats LZ4 at comparable speed at slightly better ratio.
- Rare as a user-facing format — lives mostly inside databases and filesystems.
Technical Specifications
| Specification | 7Z | LZ4 |
|---|---|---|
| MIME type | application/x-7z-compressed | application/x-lz4 |
| Compression | LZMA, LZMA2, PPMd, Bzip2, DEFLATE | — |
| Max file size | 16 EB (exabytes) | — |
| Encryption | AES-256 (content + filenames) | — |
| License | LGPL | BSD 2-Clause (library), GPL v2 (CLI) |
| Extensions | — | .lz4 |
| Algorithm | — | LZ77 variant with fast byte-level parsing |
| Typical integrations | — | Linux kernel, ZFS, Kafka, RocksDB, Cassandra |
Typical File Sizes
7Z
- Source code archive ~50% smaller than ZIP
- Linux distro installer 2–10 GB
- Virtual machine disk image 5–40 GB
LZ4
- Text file 40-60% of original
- Already-compressed data (JPEG, MP4) 99%+ (no gain)
- Database page (typical) 55-70% of original
Ready to convert?
Convert between 7Z and LZ4 online, free, and without installing anything. Encrypted upload, automatic deletion after 2 hours.
Frequently Asked Questions
7Z is an open-source archive format from the 7-Zip project. It uses the LZMA2 compression algorithm which achieves significantly better compression ratios than ZIP or RAR, making it ideal for archiving large files and datasets.
LZ4 (LZ4 Compressed) is an archive format used to bundle multiple files and folders into a single compressed file. The archive preserves the directory structure and typically reduces total size via compression. LZ4 sits in the archives & compressed family and has specific strengths around compression ratio, speed, or platform support.
7Z files open with 7-Zip (free, Windows), PeaZip (cross-platform, free), Keka (macOS), and The Unarchiver (macOS). Windows does not natively support 7Z, so third-party software is required.
7-Zip, WinRAR, The Unarchiver (macOS), and the built-in archive utilities on Windows and macOS open most LZ4 files. For command-line extraction, 7z, unar, or the format-specific tool handles LZ4 cleanly. If your extractor does not recognise LZ4, convert to ZIP first — ZIP opens on every operating system without extra software.
Use 7Z when maximum compression is the priority, such as software distribution and backups. Use ZIP when the recipient needs to open the file without installing extra software, since ZIP is natively supported everywhere.
Upload the LZ4 to KaijuConverter and pick ZIP, 7Z, TAR.GZ, or RAR as the target. Our pipeline extracts the original archive and re-compresses the contents into the target format. File permissions, timestamps, and directory structure are preserved where both formats support them.