After you enable the Brotli compression feature, static text files are compressed into Brotli files. This reduces file sizes and accelerates content delivery. This topic describes how to enable the Brotli compression feature.

Background information

Brotli is a new open source compression algorithm. After Brotli compression is enabled, Content Delivery Network (CDN) nodes can compress text files in formats such as HTML, JavaScript, and CSS when the nodes return the requested resources. Brotli compression is 15% to 25% more efficient than intelligent compression.

  • If a request includes the Accept-Encoding: br request header, Alibaba Cloud CDN uses Brotli to compress requested resources before it returns the requested resources to the client.
  • If a response from the origin server includes the Content-Encoding: br response header, it indicates that the requested resources are compressed based on Brotli.
  • If both Brotli compression and GNU zip (Gzip) compression are enabled, and the Accept-Encoding request header includes the br and gzip fields, Brotli compression takes priority.
  • If compression is enabled on the origin server, and the response includes the content_encoding response header, Brotli compression is not supported.


  1. Log on to the Alibaba Cloud CDN console.
  2. In the left-side navigation pane, click Domain Names.
  3. On the Domain Names page, find the domain name that you want to manage and click Manage in the Actions column of the domain name.
  4. In the management pane of the domain name, click Optimization.
  5. In the Brotli Compression section, turn on the Brotli Compression switch.