Thursday, August 08, 2013
Webmaster level: Intermediate
Users tell us they use smartphones to search online because it's quick and convenient, but today's average mobile page typically takes more than 7 seconds to load. Wouldn't it be great if mobile pages loaded in under one second? Today we're announcing new guidelines and an updated PageSpeed Insights tool to help webmasters optimize their mobile pages for best rendering performance.
Prioritizing above-the-fold content
Research shows that users' flow is interrupted if pages take longer than one second to load. To deliver the best experience and keep the visitor engaged, our guidelines focus on rendering some content, known as the above-the-fold content, to users in one second (or less!) while the rest of the page continues to load and render in the background. The above-the-fold HTML, CSS, and JS is known as the critical rendering path.
We can achieve sub-second rendering of the above-the-fold content on mobile networks by applying the following best practices:
- Server must render the response (< 200 ms)
- Number of redirects should be minimized
- Number of roundtrips to first render should be minimized
- Reserve time for browser layout and rendering (200 ms)
As always, if you have any questions or feedback, please post in our discussion group.