# The current state of Brotli compression

DevFeed: [The current state of Brotli compression](<https://devfeed.tech/articles/the-current-state-of-brotli-compression-41341.md>)

Original publisher: [Read original article](<https://samsaffron.com/archive/2016/06/15/the-current-state-of-brotli-compression>)

Author: Sam Saffron

Published: 2016-06-15T00:10:11Z

Content type: article

Language: en

Sources: [Sam Saffron](<https://devfeed.tech/sources/sam-saffron.md>)

Topics: [Compression](<https://devfeed.tech/topics/compression.md>), [browsers](<https://devfeed.tech/topics/browsers.md>), [Chrome](<https://devfeed.tech/topics/chrome.md>), [Firefox](<https://devfeed.tech/topics/firefox.md>), [HTTP](<https://devfeed.tech/topics/http.md>), [Caching](<https://devfeed.tech/topics/caching.md>)

Tags: [browsers](<https://devfeed.tech/tags/browsers.md>), [cache-control](<https://devfeed.tech/tags/cache-control.md>), [caching](<https://devfeed.tech/tags/caching.md>), [chrome](<https://devfeed.tech/tags/chrome.md>), [compression](<https://devfeed.tech/tags/compression.md>), [firefox](<https://devfeed.tech/tags/firefox.md>), [http](<https://devfeed.tech/tags/http.md>)

## AI overview

The article examines Brotli compression adoption in Chrome and Firefox, its restriction to HTTPS, compatibility problems with non-compliant HTTP intermediaries, and measured compression savings compared with competing approaches.

## Source excerpt

In late May 2016 Chrome pushed out Chrome 51, unlike many releases of Chrome which are complete non-events, this release has an enormous impact. Google turned on Brotli support - and they promptly backported it into Chrome 50. Pasted image1022x761 41.9 KB Firefox added support for Brotli in September 2015. They even blogged about it. 8 months later, thanks to Google, Brotli went from a compression format supported in less than 10% of global browsers to nearly 50% global adoption! Brotli is HTTPS only If you visit a site over HTTP your browser will not accept the br encoding. The reasoning for this is documented at the end of the chromium issue. pdansk I have a question. What does intermediates refer to in the reason to restrict this feature to HTTPS only? Caches? If so, this may or may not be solved by adding no-transform to Cache-Control when you send Content-Encoding: br. I don't know. I think that restricting to HTTPS is regrettable, as what you save with brotli you lose double by not having caching. kenjibaheux@chromium Intermediaries (or "middle boxes") refers to companies/infra/software meddling with the data transfer between you (the user) and the webserver. One example from SDCH that was mentioned to me (the name of the company is not relevant to the discussion so I'm hiding it): "The most extreme case of middle box was Company AcmeTelecom (fictitious name but true story), that tried to make things better when faced with unknown content encodings, by doing the following things: a) Remove the unrecognized content encoding b) Pass the (already compressed!) content through another gzip encoding pass c) Claim that the content was merely encoded as gzip" Lack of Brotli support over unencrypted HTTP is no mistake. The world is full of terribly non-compliant HTTP proxies: https://twitter.com/samsaffron/status/514538810894340097 Brotli is yet another reason for you to push for that HTTP/2 change you have been holding out on. Brotli: The New Pied Piper? When I first