Content-Encoding

An HTTP response header specifying the compression algorithm applied to the response body before transmission, with common values of gzip, br (Brotli), deflate, and zstd. Distinct from Transfer-Encoding, which handles the transport-level encoding. Clients advertise supported encodings via the Accept-Encoding request header, and servers select the best match, reducing payload size significantly for text-based content like HTML, CSS, and JSON.