Site Speed

About Site Speed

The Site Speed reports measure three aspects of latency:

  • Page-load time for a sample of pageviews on your site. You can view the data across different dimensions to see how quickly your pages loaded from a variety of perspectives (e.g. in different browsers, in different countries). No additional configuration is required to see this data. Data is available in the Overview and Page Timings reports.
  • Execution speed or load time of any discrete hit, event or user interaction that you want to track (e.g. how quickly images load, response time to button clicks). Data is available in the User Timings report.
    This requires additional set up that must be completed by a qualified developer. For details on how to add the custom timing code, follow the instructions in the Developer Guide for Universal Analytics (analytics.js) or classic Google Analytics (ga.js). You must use the same method as your collection snippet.
  • How quickly the browser parses the document and makes it available for user interaction. No additional configuration is required to see this data. Data is available in the Page Timings report, on the DOM Timings subtabs.

You can use the information in these reports to assess how well your site performs in terms of how quickly users are able to see and interact with content. You can identify areas that need improvement, and then track the extent of those improvements.

You can see the reports in Content > Site Speed.

The Overview report focuses on average page-load time by Browser, Country/Territory and Page.

The Page Timings report lets you perform detailed analysis of individual page performance. The report includes the following tabs and subtabs:

  • Explorer: Page data in the context of different primary and secondary dimensions
    • Site Usage: Basic interaction metrics like pageviews and bounce rate
    • Technical: Network and server metrics
    • DOM Timings: Document-parsing metrics
  • Distribution: Timing buckets for different metrics
  • Map Overlay: Geographic data in the context of different primary and secondary dimensions
    • Site Usage: Basic interaction metrics like pageviews and bounce rate
    • Technical: Network and server metrics
    • DOM Timings: Document-parsing metrics

The User Timings report lets your perform detailed analysis of individual resource performance (e.g. images, videos, buttons). The report includes the following tabs:

  • Explorer: Resource data in the context of different primary and secondary dimensions
  • Distribution: Timing buckets for different metrics
  • Map Overlay: Geographic data in the context of different primary and secondary dimensions

Notes

  • Site speed tracking has no impact on bounce rate for your site.
  • Site speed tracking occurs only for visits from those browsers that support the HTML5 Navigation Timing interface or have the Google Toolbar installed. Typically this includes: Chrome, Firefox 7 and above, Internet Explorer 9 and above, Android 4.0 browser and above, as well as earlier versions of Internet Explorer with the Google Toolbar installed.
  • The calculation for Average Page Load Time changed in November 2011: Average Page Load Time now includes redirection time. You may see an increase in your site's overall page load time, depending on the number and significance of redirects on your site. When you make date comparisons, please remember that data collected before November 2011 doesn't include redirection times.
  • Starting on around 16 Nov 2011, many sites saw increased Avg. Page Load Times. These inflated metrics are not a real speed issue for the sites, but a result of bugs in Firefox’s Navigation Timing implementation, specifically how the start of navigation is calculated. As a result, pages viewed in Firefox show higher values for Avg. Redirection Time, and thus Avg. Page Load Time. This was fixed as part of Firefox 9, released on 10 December 2011 and auto-updated to users over the following 3-4 weeks. If your site has higher page-load times during this period, you can determine if this is due to Firefox by checking the data along the Browser dimension.
  • By default, a fixed 1% sampling of your site visitors make up the data pool from which the page timing metrics are derived. See the Tracking Code Reference for specific details on customising the Site Speed sample rate with setSiteSpeedSampleRate().
  • Previous versions of Site Speed required a tracking-code change to add _trackPageLoadTime. Sites with the deprecated call still collect speed data at the 10% sampling rate. However, this call will be ignored in the future, and the sample rate will change to the default 1%. Consider updating your tracking code to use setSiteSpeedSampleRate() to set a higher sampling rate.

Next: Find out how to Interpret Site Speed.