Compression is a simple, effective way to save bandwidth and speed up your site.
If you’ve optimized your site and want to check if you’re actually serving up compressed content, you can make use of this free online gzip test tool.
Below is a result of a test I carried out using the tool.
As you can see in the result, Ogbongeblog homepage shrunk from 51k to 10k, almost 80% reduction in size.
I used W3 Total cache plugin for the gzip optimization.
Alternatively, you can use https://checkgzipcompression.com
You can also use Chrome to check.
In Chrome, open the Developer Tools > Network Tab (Firefox/IE will be similar). Refresh your page, and click the network line for the page itself (i.e., www.ogbongeblog.com). The header “Content-encoding: gzip” means the contents were sent compressed.
Source : How To Optimize Your Site With GZIP Compression – BetterExplained