This GZIP Compression Test tool checks whether text compression like GZIP, Brotli (br), etc. is enabled on a website or not.
You can easily enable text compresssion (GZIP, DEFLATE) on your website to improve site speed. Check out this Guide to Enable GZIP Compression on your website.
Text compression reduces the size of a web page to make it load faster. Hence, enabling text compression on a website helps improve pagespeed.
GZIP, Brotli (br), and DEFLATE are popular web supported text compression methods (formats).