EngineeringScorePerformance Larger effort
Reduce page weight
Total page weight is the sum of every byte a browser has to download to render the page: HTML, CSS, JS, images, fonts, and third-party embeds. It is a blunt but powerful metric: heavier pages take longer to become usable on every connection, and the effect is most punishing on mobile networks where bandwidth is limited and variable.
Why it matters
Heavier pages take longer to load, especially on mobile networks, and slow load times directly correlate with higher bounce rates and lower conversion.
How to fix
- 1 Compress and lazy-load images below the fold.
- 2 Remove unused JavaScript/CSS and unnecessary third-party scripts.
- 3 Audit third-party embeds (chat widgets, trackers) for ones that can be deferred or dropped.
Common mistakes
- Optimizing the initial page load but ignoring third-party scripts (chat widgets, ad tech, analytics) that often account for the largest share of weight.
- Compressing images without resizing them first, so a 4000px-wide photo is still served at a fraction of its necessary size just because it is now a smaller file format.
- Treating page weight as a one-time cleanup rather than a budget, so it creeps back up as new features and scripts get added.
How to verify
- 1 Load the page in devtools with network throttling enabled and check the total transferred size reported in the network panel.
- 2 Run the page through a performance auditing tool (e.g. Lighthouse, WebPageTest) and review its resource breakdown by type.
- 3 Re-check page weight after adding any new third-party script or embed to confirm it did not silently balloon the total.
Related checks
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