What this audit checks
Authentication & access
- Site URL reachable and returns a successful PageSpeed run (runPagespeed 200)
- PageSpeed API key present and under daily quota (no 429 on probe)
- CrUX origin record available for the publication (field data exists, not ‘origin not found’)
Core Web Vitals (CrUX field, mobile)
- Mobile LCP p75 > 4000ms (poor - readers perceive a slow page)
- Mobile INP p75 > 500ms (poor interaction responsiveness)
- Mobile CLS p75 > 0.25 (poor layout stability)
- Mobile TTFB p75 > 1800ms (slow server / origin response)
- Mobile CWV pass rate < 50% (failing Google’s ranking-relevant threshold)
Lighthouse lab quality
- Mobile Performance score < 50 (poor lab performance)
- Performance gap between mobile and desktop > 30 points (mobile-specific regression)
- SEO score < 70 (crawlability / meta gaps on a publication that lives on search)
- Accessibility score < 70 (excludes readers and risks compliance)
- Best Practices score < 70 (console errors, insecure requests, deprecated APIs)
Page weight & resource hygiene
- Total page weight > 3MB (bloat from third-party scripts / unoptimised media)
- Total Blocking Time > 600ms (main-thread work blocking interaction)
- Speed Index > 5800ms (slow visual completion)
- Render-blocking resources with > 500ms potential savings (defer / inline critical CSS/JS)
Cross-channel: performance-to-readers (the killer area)
- Origin CWV pass rate < 50% AND analytics sibling shows bounce/exit trending up on the publication (slow pages losing readers)
- Render-blocking / page-weight regression coincides with a drop in analytics sessions-to-subscribe on the same origin
- High-traffic landing path (analytics sibling) has poor mobile LCP - prioritise that template for fixes
Severity thresholds
| Signal | Warn | Critical |
|---|---|---|
gho_lcp_mobile | 2500 | 4000 |
gho_inp_mobile | 200 | 500 |
gho_cls_mobile | 0.1 | 0.25 |
gho_crux_mobile_pass | 75 | 50 |
gho_lighthouse_perf | 90 | 50 |
gho_psi_total_weight | 1572864 | 3145728 |
Data sources
GET https://pagespeedonline.googleapis.com/pagespeedonline/v5/runPagespeed- Lab Lighthouse scores + page-weight audits + embedded CrUX origin block per (URL, strategy)GET https://chromeuxreport.googleapis.com/v1/records:queryRecord- CrUX field data - origin-level p75 LCP/INP/CLS/TTFB and CWV pass rate