lz4 128

lz4 128

LangLanguage CC
License BSD
ReleasedLast Release Apr 2015

Maintained by Dapperstout, Stefan van den Oord.

lz4 128

  • By
  • Yann Collet

LZ4 - Extremely fast compression

LZ4 is lossless compression algorithm, providing compression speed at 400 MB/s per core, scalable with multi-cores CPU. It also features an extremely fast decoder, with speed in multiple GB/s per core, typically reaching RAM speed limits on multi-core systems. A high compression derivative, called LZ4_HC, is also provided. It trades CPU time for compression ratio.

Branch Status

Branch Policy:

  • The "master" branch is considered stable, at all times.
  • The "dev" branch is the one where all contributions must be merged before being promoted to master.
    • If you plan to propose a patch, please commit into the "dev" branch. Direct commit to "master" are not permitted.
  • Feature branches can also exist, for dedicated testing of larger modifications before merge into "dev" branch.


The benchmark uses the Open-Source Benchmark program by m^2 (v0.14.2) compiled with GCC v4.6.1 on Linux Ubuntu 64-bits v11.10, The reference system uses a Core i5-3340M @2.7GHz. Benchmark evaluates the compression of reference Silesia Corpus in single-thread mode.

Compressor Ratio Compression Decompression
LZ4 (r101) 2.084 422 MB/s 1820 MB/s
LZO 2.06 2.106 414 MB/s 600 MB/s
QuickLZ 1.5.1b6 2.237 373 MB/s 420 MB/s
Snappy 1.1.0 2.091 323 MB/s 1070 MB/s
LZF 2.077 270 MB/s 570 MB/s
zlib 1.2.8 -1 2.730 65 MB/s 280 MB/s
LZ4 HC (r101) 2.720 25 MB/s 2080 MB/s
zlib 1.2.8 -6 3.099 21 MB/s 300 MB/s

The LZ4 block compression format is detailed within lz4_block_format.txt.

For streaming unknown amount of data and compress files of any size, a frame format has been published, and can be consulted within the file LZ4_Frame_Format.html .