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Auditing the 10 most visited websites in the UK

Week 216.0 — 13th December '21

I've been auditing websites for their speed and page weight for well over 18 months now, and I've been curious about how the most popular websites perform. Using the same criteria (below), I've been through the top 10 for the UK and have the results below... Do they have what it takes to be featured on Sitejoy?

Sitejoy criteria

  • Fully responsive
  • Up to 200kB JavaScript transfered
  • Up to 3MB of page data transferred
  • Mobile & desktop page speed scores must be 70 or higher
  • Average page speed score across mobile & desktop must be 80 or higher

Results after auditing the top 10 websites:

RankWebsiteResponsiveJavaScript (kB transfered)Page weight (MB transfered) Pagespeed
1google.com /
(logged out)
(logged in)
(logged out)
(logged in)
(logged out)
(logged in)

Where I logged in, I attempted to use the Lighthouse feature in Chrome but it often hung or took forever. Instagram couldn't be really be audited for it's Pagespeed so I left it as unknown.

I've also marked anything that need a refresh to get it's layout to be right for the screen size as not responsive, Facebook was the only one to redirect to a mobile specific domain.


It's a sad state of affairs. Only Wikipedia would be eligible, were it not for it's dated design which offers no real inspiration.

If a million people visited google.com, that would see 1.2 terabytes of data transferred. Instagram, the worst offender here would cause around 7.8 terabytes of data. That's a factor of almost 7 between them, but I would have though the difference would have been much larger given Google's homepage offers a search bar and Instagram presents a far richer experience.

I get a lot of satisfaction auditing sites for Sitejoy and getting them featured. I just wish the larger, more popular, sites paid a lot more attention to the amount of data they're transferring.

More from 1 Thing A Week
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Quick links and commentary on interesting articles, videos and more throughout the week.

  1. 216.1 – Monday
    1. Nike Overbreak Hot Curry coolmaterial.com
  2. 216.2 – Tuesday
    1. I'm Black but look White. Here are the horrible things white people feel safe telling me. huffpost.com
  3. 216.3 – Wednesday
    1. Power Rangers Lightning Collection Mighty Morphin Megazord   £149.99 uk.hasbropulse.com
  4. 216.4 – Thursday
    1. Notifications xkcd.com
    2. Analog Waking Clock   $299 oneclock.co

Jump to notable items for Week #215, Week #217 , view the notable archive or my favourites.

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