Google PageSpeed – the loading speed of a website

In mid 2009, Google started their initiative for a faster internet “Let’s make the web faster”. This laid the foundation for another (new) ranking factor.

We focus on speed as a key requirement in product and infrastructure development, because our research indicates that people prefer faster, more responsive apps.


Instead of focussing solely on their own products and services, Google encouraged webmasters worldwide to reflect on their PageSpeed, the loading speed of their website. Just one year later, they confirmed that the PageSpeed would be added as another one of their roughly 200 ranking-factors.

Even though the ranking-factor “PageSpeed” only influences less than 1% of worldwide search requests, according to Google,

[…] the current implementation mentions that fewer than 1% of search queries will change as a result of incorporating site speed into our ranking […]Matt Cutts, Distinguished Engineer at Google

webmaster should pay attention to a fast delivery of their website’s content for the benefit of their own users and therefore optimise the loading times for their website.

We encourage you to start looking at your site’s speed — not only to improve your ranking in search engines, but also to improve everyone’s experience on the Internet.

Google Search Quality Team

Research has shown that the satisfaction of a user decreases 16% for every second of elapsed loading time. With a loading time (of the site) of 4 seconds, 25% of users will immediately leave the website again.

Part of an infographic by kissmetrics, based on research from and
Part of an infographic by kissmetrics, based on research from and

It is therefore recommended to keep an eye on the PageSpeed of your website and optimise it, if necessary.

How is the PageSpeed of a website measured?

Google mainly uses the Google toolbar data to measure the PageSpeed. This way, they can measure the average connectivity of a website for all users with different internet connections and speeds. A website does not necessarily have to have slower loading speeds because of large pictures or many lines in the HTML source code, the connection of the webserver could also be the crucial factor, among others. In order to also include such possibile influences, Google uses the toolbar data.

Furthermore, when determining loading times, Google will not only look at the HTML-, CSS- and JavaScript-files, but also measure the time it takes for picture integrations to load and ignore the cache specifications for a website.

Core Web Vitals in 2021

Google has announced that the Core Web Vitals will be a ranking factor in 2021. Core Web Vitals not only measure page loading speed but more detailed elements such as the time taken for usable content to appear and formatting ‘shifts’ that might occur during loading.

How does Google determine page speed?

How does Google determine page speed?

Video explanation by Google on the innitiative “PageSpeed”

Let’s make the web faster

Browsing the web should be as fast as turning the pages of a magazine to enable the next generation of rich web applications.

Further information by Google on the subject

Graphic on the loading time of a website and corresponding user signals

Steve Paine