lz4

Extremely fast lossless compression algorithm prioritizing speed over ratio.

Author: Yann Collet
Alternative to: gzip (See 2 others)
Language: C
This page last updated:

lz4 is a lossless compression algorithm focused on compression and decompression speed rather than compression ratio. It achieves compression speeds over 500 MB/s per core and decompression speeds in multiple GB/s, often reaching RAM speed limits on multi-core systems.

Features

  • Compression speed >500 MB/s per core; decompression up to ~5 GB/s
  • LZ4_HC high-compression mode trades speed for better ratios while keeping decompression fast
  • Tunable acceleration factor to trade compression ratio for even faster speeds
  • Dictionary compression support compatible with zstd dictionaries
  • Streaming support for arbitrarily large files via the LZ4 frame format
  • Widely used in Linux kernel, Redis, MySQL, Hadoop, and other infrastructure

Basic usage

# Compress a file.
lz4 file.txt

# Decompress a file.
lz4 -d file.txt.lz4

# Use high-compression mode.
lz4 -9 file.txt

# Pipe compression.
tar cf - dir/ | lz4 > archive.tar.lz4

Availability

Available on Linux, macOS, and Windows.