The first step in optimizing any process is to establish and obtain an accurate set of measurement data. In the context of optimizing the user experience on the web, it means that we need to measure the speed of a page as seen by your real users: users network, device type and speed, geographic location, cache sizes, and a dozen other factors all come into play.
Luckily, the Site Speed reports in Google Analytics provide most of this data to us already. The new Web Timing standard, which is already implemented by most modern browsers, allows Google Analytics to gather detailed latency data for a sample of requests across a dozen different dimensions. To see this data for your site, navigate to your Google Analytics account and look for the new “Site Speed” reports under the “Content” section - there is no additional instrumentation required on your behalf.
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