Guides
How to measure a site and read what comes back. Each guide carries at least one number from our own audit base, because the steps themselves are documented by Google and repeating them is not worth your time or ours.
How to run a Lighthouse speed test
Three ways to run it — Chrome DevTools, PageSpeed Insights and the command line — and what to do about the fact that the score moves between runs.
18% of our mobile measurements put two rounds in different bands Servinggzip or Brotli: what to switch on, and what it costs
Maximum-quality Brotli on our own shared host took Speed Index from 1.6 s to 3.8 s. How to check what your server sends, and why the cheaper algorithm won here.
1.6 → 3.8 s Speed Index after enabling per-request Brotli-11One rule for this section: a guide gets published only if we can put something measured into it. Where a step is just a step, we link Google's own documentation rather than retype it. That is why this section grows slowly.
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