Google PageSpeed Insight major update happened on November 12th without any announcement.  In this latest release, the approach for testing and checking the website was completely revamped. These changes may affect the whole industry of website development because during the last 6-7 years this was one of the major tools for checking the speed and optimization of the websites.

What Changed?

All previous metrics were completely removed. Right now Google uses the metrics from their own open source project called Lighthouse. This tool is integrated into google chrome dev tools. Everything is evaluated based on the speed, not implementation rules.

The main difference in the metrics approach is this – your website gets points for the speed instead of for the rules implemented. The page speed loading is estimated via a few timing metrics – how quickly it takes to start the website drawing, when a user can start clicking different elements, how all the UI elements are stolen until all assets are loaded, and when the site is completely ready for use.

Before, after checking, the tool would provide suggestions, but the implementation of those suggestions never guaranteed more speed points. So, now your developer should analyze the report more carefully and implement his vision for the website speed improvements.

New Metrics

Let’s see the new metrics on our own website for an example.

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Time to interactive

This is the most important metric. It tells when the site is ready for use.

This event comes when:

  • the page is fully drawed
  • all elements handler is registered
  • the response of user actions is less than 50ms

Speed Index

Shows how much time it is required for all the content to load (images, video, etc). For checking used module Speedline. That is the time when the browser stops changing visually. To check this, a visual image comparison is used.

First Contentful Paint

An interval between the start of the page loading and showing the first UI element.

First CPU Idle

This metric show – when your CPU is free from page drawing and ready to accept manual inputting. This moment comes when:

  • most of UI elements are interactive
  • page reacts to user action without a big latency
  • the response of user actions is less than 50ms

First Meaningful Paint

The time when you see the main site content. Requirements for this event:

  • main page changes were done
  • fonts were loaded

Estimated Input Latency

The score above is an estimate of how long your app takes to respond to user input, in milliseconds, during the busiest 5s window of page loading. If your latency is higher than 50 ms, the users may perceive your app as laggy.

Conclusion

Each metric is compared with the performance of all evaluated sites. If you have it better than 98% of the websites, you get 100 points. If it is better than 75% of the websites – you get 50 points.

As we can see,  this new Google PageSpeed Insights version is not very usable yet. For the same website, it returns different results. But in any case, all website should prepare for the new metrics from Google.

If you have a question or need a help with a true, in-depth analysis of your website –  feel free to get in touch below.