Google’s compression algorithm Brotli succeeds Zopfli

Google releases a new compression algorithm called Brotli two years after Zopfli. Where Zopfli was still compatible with Deflate, Brotli is a completely new data format. The new format should be able to achieve a 20 to 26 percent higher compression ratio over Zopfli.

A proprietary study by the Google developers showed that Brotli is about as fast as zlib’s Deflate implementation, while yielding slightly smaller files on average than lzma and bzip2. The name of the new open source compression algorithm, like Zopfli, is again derived from a Swiss bakery product, Brötli, which means ‘sandwich’ in Swiss German.

Google developed the new algorithm following the development of Zopfli. According to its own research paper, after Zopfli’s wide adoption, “noises were heard” that it would be time to start leaving the Deflate file format and invent a new form. With Brotli, the internet giant is attempting to create a lossless compression format that is fundamentally different from Deflate.

For Google and others, every little bit helps because smaller files make pages load faster. The hope is that the format will be supported by all major web browsers in the future as the format would benefit mobile connection users.