What is making my website slow?

Updated 2026-10-16

Short answer: slow sites are almost always slow for a few specific reasons: a huge image, a heavy script, files that block the page from showing, files that aren't cached, or a slow outside service. Finding which one matters more than a single speed score.

How to check it yourself

  1. Open developer tools, then Network, and reload with the cache disabled.
  2. Sort by size and look at the largest images and scripts.
  3. Check which files load before the page can show, and which come from other services.
  4. Run the page through Google PageSpeed Insights for real-visitor data, if Google has it for your site.

What Preventionlabs shows

Every report breaks down what makes your homepage slow: total size, the largest images and scripts, scripts that block the page, caching lifetimes and files from other services, and how long the page takes to download at Lighthouse's slow-mobile speed against Google's 2.5-second mark. Where Google publishes it, it adds what real visitors on phones got over the last 28 days from the Chrome UX Report.

Price

First report free, no card needed. Then A$50 a month, up to 10 domains.

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