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Performance

Core Web Vitals, payload weight, render-blocking assets, and caching posture.

How fast your site feels to real users, measured across 4–5 representative pages rather than the homepage alone - so a fast landing page can't mask a slow application.

Performance is the only category scored on a sliding scale: metrics award partial credit rather than a binary pass/fail.

Core Web Vitals

MetricGoodNeeds workPoor
LCP - Largest Contentful Paint≤ 2.5s≤ 4s> 4s
CLS - Cumulative Layout Shift≤ 0.1≤ 0.25> 0.25
TBT - Total Blocking Time≤ 200ms≤ 600ms> 600ms

LCP carries the single largest weight of any check in FlawPilot. It's usually dominated by one thing - an unoptimised hero image or a render-blocking font.

Loading speed

MetricGoodNeeds workPoor
TTFB - Time to First Byte≤ 800ms≤ 1800ms> 1800ms
FCP - First Contentful Paint≤ 1.8s≤ 3s> 3s
Speed Index≤ 3.4s≤ 5.8s> 5.8s

A slow TTFB points at the server or origin, not the front end - check caching and CDN coverage before optimising assets.

Composite

An overall performance score across the sampled pages also contributes to the category result.

Reading a performance result

Because several pages are sampled, a mid-range score often means one slow route rather than a uniformly slow site. Look at the per-page breakdown before optimising - the fix is usually specific to a single template.

Measure after cache warm-up

A first scan against a cold CDN can under-report. If a result looks anomalous, rescan once the cache is warm.