WPT load times vastly different from other speed tests

[kpmcgee73]

Hi Joseph,

Thanks for the insight, my apologies for the different sites.

Here's a better example:

On my live site I'm getting a page load of 4.9 secs with webpagetest:

http://www.webpagetest.org/result/151008_HC_T7M/

whilst the test with gtmetrix shows a page load of 1.3 secs
925ms with Pingdom: http://tools.pingdom.com/fpt/#!/byx21z/h...rloom.com/

https://gtmetrix.com/reports/www.vintage...m/bsj4Hci0

Testing a few times I get the same big difference. I'll assume webpagetest is correct. there is still a slight difference in the page size, which seems strange.

Any ideas why webpagetest is different, perhaps the others are just inaccurate?

thanks