When I analyze the website's page load speed in Chrome I can see the wait time (where the return response files of the sever are being generated) is 55ms and total page load time is 1 second or much less.  When I run the test via `https://www.pingdom.com/`, `http://gtmetrix.com/`, or the Google speed test tool, the wait time is 1.8 seconds or more and total page load time is 3 seconds or more.

The page is fully cached and the cache has been warmed.

Any ideas on why this would happen?  The efforts I have made so Google would see my site as fast loading will be lost.

Please don't comment about all other optimization tips like gzip and minifying css files.  I am purely asking about the wait time and/o its effects on ttfb.