Infinita Lab
Web Performance
Metrology Testing Laboratory Services
Live PageSpeed Insights report · https://infinitalab.com/metrology-testing-service/
Perf · Mobile
53
/ 100
Perf · Desktop
99
/ 100
Mobile LCP
4.5s
target < 2.5s
Mobile TBT
949ms
target < 200ms
Page weight
3.2 MB
mobile
The headline
On mobile this page scores 53 against 99 on desktop. The gap is driven by a 1.8 MB mobile JavaScript bundle producing 949ms of main-thread blocking and 4.1s of CPU work. Desktop, loading only 10 KB of JavaScript, is effectively perfect. Real-user field data (CrUX) still rates the URL as failing Core Web Vitals.
Scores & Core Web Vitals (lab)
| Metric | Mobile | Desktop | Target |
|---|---|---|---|
| Performance | 53 | 99 | 90+ |
| Accessibility | 95 | 95 | 90+ |
| Best Practices | 69 | 100 | 90+ |
| SEO | 92 | 92 | 90+ |
| Largest Contentful Paint | 4.5s | 0.8s | < 2.5s |
| Cumulative Layout Shift | 0.02 | 0.03 | < 0.1 |
| Total Blocking Time | 949ms | 0ms | < 200ms |
| First Contentful Paint | 3.0s | 0.8s | < 1.8s |
| Speed Index | 6.0s | 0.9s | < 3.4s |
| Time to First Byte | 285ms | 9ms | < 0.8s |
Real-user field data (CrUX, 28-day)
LCP p75
3.6s
INP p75
182ms
CLS p75
0.01
CWV assessment
Fail
Page composition
| Metric | Mobile | Desktop |
|---|---|---|
| Total page weight | 3.2 MB | 0.4 MB |
| Images | 0.6 MB | 0.1 MB |
| JavaScript | 1.8 MB | 0.0 MB |
| Requests (total) | 143 | 27 |
| Script requests | 43 | 3 |
| Image requests | 41 | 11 |
| CPU / main-thread | 4.1s | 0.4s |
Prioritised recommendations
P1Cut the mobile JavaScript bundle
Mobile loads 1.8 MB of JavaScript, burning 4.1s of CPU and 949ms of blocking time. PSI flags ~600ms of savings from unused JavaScript alone.
P2Trim unused CSS
PSI flags ~300ms of savings from unused CSS on mobile. Purge and split stylesheets so only above-the-fold CSS blocks render.
P3Clean up mobile Best Practices
Mobile Best Practices is 69 (desktop is 100). Resolve console errors and deprecated API usage flagged by Lighthouse.
Independent of DebugBear. This is a fresh Google PageSpeed Insights run by Claude, not from the DebugBear project. Numbers differ from the 17 Jul DebugBear snapshot (which showed mobile Perf 62, TBT 7.5s) because of engine, throttling and timing differences and the tracking rollout since then. The mobile-vs-desktop pattern is identical either way.
Source: Google PageSpeed Insights API (Lighthouse lab + CrUX field), 22 Jul 2026, 00:54. Mobile emulation: Moto G4-class, Slow 4G. Lab results are single-run and vary run to run.