Test Mobile Load Time Under 3 Seconds

Task Library

Measures real mobile load speed with PageSpeed Insights and Lighthouse to confirm the site loads in under 3 seconds, where most local-service visitors arrive.

Category: Website QA Audit

Use this when running Layer 1 (Digital Plumbing Checks) of the Website QA Audit – most local-service traffic is mobile, and slow pages lose leads before they load.

Inputs

  • Site URL plus the top pages by traffic (homepage, key service pages, top blog posts)
  • Google PageSpeed Insights (pagespeed.web.dev) or Lighthouse in Chrome DevTools
  • The audit report/spreadsheet for logging results

Steps

  1. Run the homepage through Google PageSpeed Insights and read the Mobile tab, not Desktop.
  2. Record Largest Contentful Paint (LCP) – the practical "loaded" moment – plus the overall performance score; pass requires LCP under 3.0 seconds on mobile.
  3. Repeat for each key service page and the top 2-3 blog posts so the result reflects real templates, not just the homepage.
  4. Where a page fails, capture the top Opportunities list (oversized images, render-blocking scripts, missing caching) as the fix punch list.
  5. Re-run any failing page once to rule out a one-off test fluke; keep the worse of the two runs as the recorded result.
  6. Log LCP, performance score, and the fix list per page in the audit report.

Definition of done (QA checklist)

  • Every checked page records mobile LCP under 3.0 seconds in PageSpeed Insights/Lighthouse
  • Failing pages have a named fix list pulled from the report's Opportunities section
  • Scores and screenshots logged in the audit report, linked back to /website-qa-audit

Example(s)

  • Example needed – run the Meta-Article Prompt after first real run.

File in the zip: skills/website-qa-audit/test-mobile-load-time-under-3-seconds.md. Download the Task Library zip.

Index: Task Library. Article guidelines.

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