Now 90% of Sites Get Better PageSpeed Insights Scores with Lighthouse 10

The Time to Interaction (TI) score has been eliminated in Lighthouse 10, as stated by Google Chrome, which is a significant shift. 

According to tests, most websites will notice an improvement in their performance scores, with more than half of those websites seeing an improvement of over 5 points.

PageSpeed Insights (PSI)

PageSpeed Insights (PSI) reports on a page's user experience on desktop and mobile devices and offers recommendations for how to make that page better.

For a page, PSI offers both lab and field data. Because it is gathered in a controlled environment, lab data is helpful for troubleshooting problems. 

Yet, it might miss bottlenecks in the actual world. Field data has a more constrained set of metrics but is useful for capturing authentic, real-world user experience.

Time To Interactive – TTI

The Time to Interactive score calculates how long it takes for site users to able to interact with a page. When a user can perform actions like clicking a button or using the site navigation is determined by the score, a multi-step algorithm that measures the resource loading.

Time To Interactive has been eliminated because other metrics, including Largest Contentful Paint (LCP), Speed Index, and Total Blocking Time is taken as a whole, are stronger indicators of how fully loaded a webpage seems.

According to the Chrome blog post: 

"A count of current network requests is typically not as good a heuristic for determining how loaded a page's contents feel as Largest Contentful Paint (LCP) and Speed Index. While not a direct proxy, Total Blocking Time (TBT) manages lengthy tasks and main-thread availability more effectively, and it tends to correlate better with Core Web Vitals as observed in the field."

90% of websites will have improved scores, and 50% of websites will experience performance gains of more than 5 points, according to tests done on more than 13 million web pages.

When Can We Expect the Lighthouse 10 Modifications?

The PageSpeed Insights tool now contains the Google Lighthouse updates. The latest version of Lighthouse 10 is also available in Chrome's Canary testing version.

Lighthouse 10 will likely be available when Chrome 112 launches on March 29, 2023, as currently planned. Chrome 110 is essentially the most recent model.