On a purely compression algorithm front, the recently format-stabilized [1] zstd [2] beats the pants down Brotli, in terms of compression speed, decompression speed, and compression ratio. Zstd isn't some random effort either, but a more flexible (in terms of compression time-for-ratio) effort by the creator of the popular and insanely fast lz4 compressor[3].

Brotli's fastest compression is slightly faster than zstd's. Zstd decompresses faster, but neither is slow. Zstd can use sliding window size longer than 16 MB, in brotli this is limited to 16 MB to have guarantees of the maximum resource use at decoding time. Zstd's longer sliding window helps with the longest files (16 MB+), and often benchmarking is done with 100 MB or even 1 GB files.

Brotli compresses usually more, and quite a lot more on shorter files. Try with cp.html, sparc sum or xargs.1. Brotli compresses these 9-19 % more densely on the following benchmark:

https://quixdb.github.io/squash-benchmark/unstable/

Note, that on this benchmark brotli is always limited to the 4 MB sliding window. Other algorithms are run with wider windows, too. This will make brotli seem worse on large files (4+ MB).

blank_state

> Brotli's fastest compression is slightly faster than zstd's.

Come on, this is not serious.

Brotli's fastest compression algorithm is still significantly slower than zstd. And more importantly, it compresses _much worse_.

For a 3rd party evaluation, one can try [TurboBench](https://github.com/powturbo/TurboBench) or even [lzbench](https://github.com/inikep/lzbench) which are open-sourced. Squash introduces a wrapper layer with distortions which makes it less reliable, and more complex to use and install, quite a pity given the graphical presentation is very good. I'm interested in speed, and in this area, all benchmarks point in the same direction : for a given speed budget, Zstandard offers better ratio (and decompresses much faster).