Free HTTP Compression Check - check sites for Gzip compression.
HTTP compression is a capability that can be built into web servers and web clients to make better use of available bandwidth, and provide greater transmission speeds between both.
HTTP data is compressed before it is sent from the server: compliant browsers will announce what methods are supported to the server before downloading the correct format; browsers that do not support compliant compression method will download uncompressed data. Compression as defined in RFC 2616 can be applied to the response data from the server (but not to the request data from the client).
The most common compression schemas include gzip and deflate, however a full list of available schemas is maintained by IANA. Additionally, third parties develop new methods and include them in their products (e.g. the Google Shared Dictionary Compression Over HTTP (SDCH) schema implemented in Google Chrome browser and used on certain Google servers).