The Content-Encoding
header indicates which algorithm is been used for this message.
Valid values for the Content-Encoding
header include:
Value | Meaning | Standard |
---|---|---|
gzip |
A format using the Lempel-Ziv coding (LZ77), with a 32-bit CRC. This is originally the format of the UNIX gzip program. The HTTP/1.1 standard also recommends that the servers supporting this content-encoding should recognize |
RFC 1952 |
compress |
A format using the Lempel-Ziv-Welch (LZW) algorithm. The value name was taken from the UNIX compress program, which implemented this algorithm. Like the compress program, which has disappeared from most UNIX distributions, this content-encoding is used by almost no browsers today, partly because of a patent issue (which expired in 2003). |
HTTP/1.1 |
deflate |
Using the zlib structure (defined in RFC 1950), with the deflate compression algorithm (defined in RFC 1951). | RFC 1950 and RFC 1951 |
identity |
Indicates the identity function (i.e. no compression, nor modification). This token, except if explicitly specified, is always deemed acceptable. | HTTP/1.1 |
br |
A format using the Brotli algorithm | Experimental |
* | This wildcard represents any content-encoding not explicitly specified in the header | HTTP/1.1 |