Hugely different performance score in PageSpeed Insights and Lighthouse

user_1086197 0
Viewed 1719

After deploying a fairly fast website, I ran it through PageSpeed Insights where it only got a performance score of around 25. At the same time, the exact same page ranks 85 in the Lighthouse performance inside Edge.

I know that the PageSpeed is likely loading the pages from the US while my hosting is located in Germany, and that the Lighthouse makes use of my connection - and since I'm much closer to the server, I likely get better results because of that.

However, with performance being one of key metrics for rating a page, I can't not ask - how is this being evaluated in the real world? Should I rely more on the US-based PageSpeed or the local Lighthouse?

Note: The page is already pretty optimized, with deferred JS, minified JS & CSS, lazy loading images, compressed images and all the other nice things.

pagespeed-insights lighthouse pagespeed
2 Answers

As this question is being read a lot I thought I would summarise the comments between OP and I into an answer.

For some reason Lighthouse in Edge is reporting a much higher score than Lighthouse in other browsers.

I checked that the settings were the same for Edge as they were in Chrome and Vivaldi and ran some tests on numerous websites.

Chrome and Vivaldi were within 10% of each other but edge was scoring as much as 200% higher scores and faster FCP times etc.

As such I would not recommend using Edge Lighthouse at time of writing as it will make you think your site is performing better than it actually is.

More importantly it may not show items that need fixing within the "opportunities" and "diagnostics" sections that rely on timings and although the score is not important a lot of these recommendations can be.

I will try and update this answer if the discrepancy between Edge and Other Webkit browsers changes.

user_27028940

There is difference in PS scored of your website even when Checked on Chrome(normal mode and in incognito mode). enter image description here

enter image description here

The only reason i can think of is of Cache plugin on your website. Disable and test again for PS score. Also the thing to note:

All tests are run using a simulated mobile device, throttled to a fast 3G network & 4x CPU slowdown. https://web.dev/measure/

So website in general are faster than what PageSpeed shows.

user_52080770
Related