Home / Check catalog / 6. Schema, Local, Trust, Deep Audit / 6.32 Performance / Core Web Vitals / Caching / CDN / Rendering Cost / AI-Speed Signal Suite

6.32 Performance / Core Web Vitals / Caching / CDN / Rendering Cost / AI-Speed Signal Suite

200 checks in Schema, Local, Trust, Deep Audit. Automated Its subsection has a live automated checker in the engine.

Core Web Vitals — LCP, CLS, INP, TTFB (the Fundamentals)

ID	Check	Passes when	Weight	Runs
6.32.01	Validate LCP element detected correctly	Correct	Critical	Deterministic
6.32.02	Validate LCP < 2.5s on mobile	< 2.5s	Critical	Deterministic
6.32.03	Validate LCP image optimized (compressed, modern format)	Optimal	Critical	Deterministic
6.32.04	Validate TTFB < 200ms global average	< 200ms	Critical	Deterministic
6.32.05	Validate no server-side bottlenecks raising TTFB	Clean	Critical	Deterministic
6.32.06	Validate CLS < 0.10	< 0.10	Critical	Deterministic
6.32.07	Validate no layout shifts caused by ads/widgets	None	Critical	Deterministic
6.32.08	Validate INP measured < 200ms	< 200ms	Heavy	Deterministic
6.32.09	Validate FID < 100ms	< 100ms	Heavy	Deterministic
6.32.10	Validate no long tasks > 200ms	None	Heavy	Deterministic

Server Response Stability & Global Latency

ID	Check	Passes when	Weight	Runs
6.32.11	Validate server latency consistent globally	Consistent	Critical	Deterministic
6.32.12	Validate CDN POPs reduce global latency	Effective	Critical	Deterministic
6.32.13	Validate server supports HTTP/2 or HTTP/3	Supported	Heavy	Deterministic
6.32.14	Validate no major slowdowns in certain regions	Smooth	Heavy	Deterministic
6.32.15	Validate cache HIT ratio high	> 70%	Heavy	Deterministic
6.32.16	Validate routing stable during load spikes	Stable	Medium	Deterministic
6.32.17	Validate no DNS-level delays	Low	Medium	Deterministic
6.32.18	Validate TCP/QUIC handshake times low	Low	Medium	Deterministic
6.32.19	Validate CDN correctly caches static assets	Correct	Medium	Deterministic
6.32.20	Validate CDN edge TTL correctly configured	Correct	Medium	Deterministic

Rendering Pipeline — First Paint, First Contentful Paint

ID	Check	Passes when	Weight	Runs
6.32.21	Validate FCP < 1.8s mobile	<1.8s	Heavy	Deterministic
6.32.22	Validate render-blocking JS minimal	Minimal	Heavy	Deterministic
6.32.23	Validate render-blocking CSS minimal	Minimal	Heavy	Deterministic
6.32.24	Validate critical CSS extracted	Extracted	Heavy	Deterministic
6.32.25	Validate above-the-fold content rendered early	Early	Heavy	Deterministic
6.32.26	Validate JS executed after paint where possible	Deferred	Medium	Deterministic
6.32.27	Validate CSS delivered with media queries where possible	Efficient	Medium	Deterministic
6.32.28	Validate no heavy webfonts block rendering	Clean	Medium	Deterministic
6.32.29	Validate preload hints used properly	Correct	Medium	Deterministic
6.32.30	Validate preconnect to required origins	Present	Medium	Deterministic

JavaScript Cost, Main Thread Work & Execution Time

ID	Check	Passes when	Weight	Runs
6.32.31	Validate total JS payload < 300KB	<300KB	Critical	Deterministic
6.32.32	Validate JS execution time minimal	Minimal	Critical	Deterministic
6.32.33	Validate no JS bundles > 200KB	None	Heavy	Deterministic
6.32.34	Validate unused JS minimal	Minimal	Heavy	Deterministic
6.32.35	Validate main-thread blocking time < 200ms	<200ms	Heavy	Deterministic
6.32.36	Validate third-party JS deferred or blocked	Deferred	Heavy	Deterministic
6.32.37	Validate modules used instead of legacy JS	Modern	Medium	Deterministic
6.32.38	Validate hydration cost low	Low	Medium	Deterministic
6.32.39	Validate requestIdleCallback used appropriately	Efficient	Medium	Deterministic
6.32.40	Validate no synchronous JS blocking the thread	Clean	Medium	Deterministic

Resource Loading, Caching & Network Waterfall

ID	Check	Passes when	Weight	Runs
6.32.41	Validate number of requests < 60	<60	Heavy	Deterministic
6.32.42	Validate request grouping optimized	Efficient	Heavy	Deterministic
6.32.43	Validate caching headers max-age configured	Correct	Heavy	Deterministic
6.32.44	Validate static assets cached for 30+ days	Correct	Heavy	Deterministic
6.32.45	Validate resource prioritization correct	Correct	Medium	Deterministic
6.32.46	Validate HTTP compression (gzip/br) utilized	Enabled	Medium	Deterministic
6.32.47	Validate JS bundles split intelligently	Split	Medium	Deterministic
6.32.48	Validate third-party resources asynchronous	Async	Medium	Deterministic
6.32.49	Validate caching not overridden accidentally	Stable	Medium	Deterministic
6.32.50	Compute partial Performance score for Chunk 1	Complete	Medium	Deterministic

Image Optimization — Formats, Responsive, Transformations

ID	Check	Passes when	Weight	Runs
6.32.51	Validate responsive image srcset implemented	Present	Critical	Deterministic
6.32.52	Validate WebP/AVIF served where supported	Modern	Critical	Deterministic
6.32.53	Validate oversized images avoided (no >2x container size)	Correct	Critical	Deterministic
6.32.54	Validate lazy loading for off-screen images	Enabled	Heavy	Deterministic
6.32.55	Validate LQIP/placeholder support	Present	Heavy	Deterministic
6.32.56	Validate background images optimized	Optimized	Heavy	Deterministic
6.32.57	Validate image CDN transformations cached	Cached	Medium	Deterministic
6.32.58	Validate no unoptimized GIFs	None	Medium	Deterministic
6.32.59	Validate hero images preloaded	Preloaded	Medium	Deterministic
6.32.60	Validate images compressed to <150KB where possible	Compressed	Medium	Deterministic

Font Performance — Weight, Delivery, Loading Strategy

ID	Check	Passes when	Weight	Runs
6.32.61	Validate font-display: swap used	swap	Critical	Deterministic
6.32.62	Validate no base64 encoded giant fonts	Clean	Critical	Deterministic
6.32.63	Validate subset fonts (latin, latin-ext) loaded efficiently	Efficient	Heavy	Deterministic
6.32.64	Validate unnecessary font weights removed	Lean	Heavy	Deterministic
6.32.65	Validate preload for primary font files	Preloaded	Heavy	Deterministic
6.32.66	Validate fallbacks defined properly	Present	Medium	Deterministic
6.32.67	Validate no FOIT (Flash of Invisible Text)	None	Medium	Deterministic
6.32.68	Validate no FOUT longer than 300ms	Minimal	Medium	Deterministic
6.32.69	Validate local() font sources utilized	Utilized	Medium	Deterministic
6.32.70	Validate variable fonts used where appropriate	Optimal	Medium	Deterministic

CSS Optimization — Critical Path, Unused CSS, Delivery

ID	Check	Passes when	Weight	Runs
6.32.71	Validate critical CSS extracted	Extracted	Critical	Deterministic
6.32.72	Validate unused CSS minimal (<20%)	Minimal	Critical	Deterministic
6.32.73	Validate CSS size < 200KB (total)	<200KB	Heavy	Deterministic
6.32.74	Validate CSS split by routes/components	Split	Heavy	Deterministic
6.32.75	Validate no @import statements in CSS	Clean	Heavy	Deterministic
6.32.76	Validate minified CSS used everywhere	Yes	Medium	Deterministic
6.32.77	Validate no blocking CSS loaded in head unnecessarily	Clean	Medium	Deterministic
6.32.78	Validate tailwind/purgecss removing unused classes	Effective	Medium	Deterministic
6.32.79	Validate above-the-fold CSS inline	Inline	Medium	Deterministic
6.32.80	Validate dark-mode/light-mode CSS logic efficient	Efficient	Medium	Deterministic

Advanced Network Optimization — Prefetch, Preconnect, DNS-Prefetch

ID	Check	Passes when	Weight	Runs
6.32.81	Validate preconnect for fonts, CDN, APIs	Present	Heavy	Deterministic
6.32.82	Validate dns-prefetch correct for external domains	Correct	Heavy	Deterministic
6.32.83	Validate prefetch for next-page navigation	Enabled	Heavy	Deterministic
6.32.84	Validate prerender used when safe	Used	Heavy	Deterministic
6.32.85	Validate no unnecessary preloads	Clean	Medium	Deterministic
6.32.86	Validate fetchpriority used appropriately	Correct	Medium	Deterministic
6.32.87	Validate network requests combined where possible	Combined	Medium	Deterministic
6.32.88	Validate no duplicate network requests	None	Medium	Deterministic
6.32.89	Validate HTTP/2 multiplexing used correctly	Correct	Medium	Deterministic
6.32.90	Validate connection reuse effective	Effective	Medium	Deterministic

Rendering Cost — Hydration, Reactivity, Component Complexity

ID	Check	Passes when	Weight	Runs
6.32.91	Validate hydration < 150ms for SSR apps	Fast	Heavy	Deterministic
6.32.92	Validate component tree depth reasonable	Optimal	Heavy	Deterministic
6.32.93	Validate expensive components lazy-loaded	Lazy	Heavy	Deterministic
6.32.94	Validate no unnecessary reactivity triggers	Clean	Heavy	Deterministic
6.32.95	Validate reactive frameworks (React/Vue/Svelte) optimized	Optimized	Medium	Deterministic
6.32.96	Validate memoization/shouldUpdate used correctly	Correct	Medium	Deterministic
6.32.97	Validate hydration warnings absent	None	Medium	Deterministic
6.32.98	Validate JS frameworks configured for production mode	Correct	Medium	Deterministic
6.32.99	Validate bundle analyzer shows no critical regressions	Clean	Medium	Deterministic
6.32.100	Compute partial Performance score for Chunk 2	Complete	Medium	Deterministic

Caching Architecture — Browser, CDN, Server, Edge

ID	Check	Passes when	Weight	Runs
6.32.101	Validate browser caching strategy for HTML, JS, CSS	Correct	Critical	Deterministic
6.32.102	Validate CDN caching rules for static assets	Effective	Critical	Deterministic
6.32.103	Validate server cache not serving outdated HTML	Fresh	Critical	Deterministic
6.32.104	Validate cache invalidation occurs on deploy	Automatic	Heavy	Deterministic
6.32.105	Validate stale‑while‑revalidate tuned correctly	Optimal	Heavy	Deterministic
6.32.106	Validate ETag/Last‑Modified headers present	Present	Heavy	Deterministic
6.32.107	Validate service worker cache rules correct	Aligned	Medium	Deterministic
6.32.108	Validate no cache poisoning vectors	Clean	Medium	Deterministic
6.32.109	Validate CDN edge caching for heavy images	Cached	Medium	Deterministic
6.32.110	Validate static pages cache-hit ratio >75%	>75%	Medium	Deterministic

CDN Optimization — GEO Distribution, Pops, Latency

ID	Check	Passes when	Weight	Runs
6.32.111	Validate global POP distribution covers target regions	Covered	Critical	Deterministic
6.32.112	Validate CDN routing not bypassing edges	Correct	Heavy	Deterministic
6.32.113	Validate cache-miss rate < 30%	<30%	Heavy	Deterministic
6.32.114	Validate CDN purge works instantly	Functional	Heavy	Deterministic
6.32.115	Validate geo-steering for API endpoints	Efficient	Medium	Deterministic
6.32.116	Validate CDN fallback routing stable	Stable	Medium	Deterministic
6.32.117	Validate mobile users routed to nearest POP	Correct	Medium	Deterministic
6.32.118	Validate HTTP/3 served via CDN	Enabled	Medium	Deterministic
6.32.119	Validate edge KV / storage functioning (if used)	Functional	Medium	Deterministic
6.32.120	Validate origin failover configured correctly	Correct	Medium	Deterministic

Backend & API Performance — Database, Server, Queues

ID	Check	Passes when	Weight	Runs
6.32.121	Validate database query time < 50ms	<50ms	Heavy	Deterministic
6.32.122	Validate API response time < 150ms	<150ms	Heavy	Deterministic
6.32.123	Validate backend CPU usage < 70% under load	Optimal	Heavy	Deterministic
6.32.124	Validate no API endpoints causing slow TTFB	Clean	Heavy	Deterministic
6.32.125	Validate queue processing < 200ms avg	Fast	Medium	Deterministic
6.32.126	Validate DB indexes present on frequently queried fields	Indexed	Medium	Deterministic
6.32.127	Validate N+1 queries minimized	Minimal	Medium	Deterministic
6.32.128	Validate connection pooling optimized	Optimal	Medium	Deterministic
6.32.129	Validate backend error rate < 1%	<1%	Medium	Deterministic
6.32.130	Validate cold start times minimized (serverless)	Reduced	Medium	Deterministic

AI-Speed Signals — Crawl Budget, Render Cost, Consistency

ID	Check	Passes when	Weight	Runs
6.32.131	Validate server responds deterministically for AI crawlers	Deterministic	Critical	Deterministic
6.32.132	Validate no excessive JS blocking AI render	Minimal	Critical	Deterministic
6.32.133	Validate crawl budget not wasted on duplicate URLs	Efficient	Heavy	Deterministic
6.32.134	Validate AI crawlers receive meaningful HTML early	Early	Heavy	Deterministic
6.32.135	Validate AI speed signals strong (fast TTFB, no loops)	Strong	Medium	Deterministic
6.32.136	Validate no AI-crawling traps (redirect loops, JS-only nav)	Clean	Medium	Deterministic
6.32.137	Validate AI gets consistent LCP layout across visits	Consistent	Medium	Deterministic
6.32.138	Validate important schema delivered early in HTML	Early	Medium	Deterministic
6.32.139	Validate multilingual pages not fragmented across parameters	Clean	Medium	Deterministic
6.32.140	Validate crawlable sitemaps stable & up-to-date	Stable	Medium	Deterministic

Mobile & Low-Power Performance — Throttled Cpu, Battery Mode

ID	Check	Passes when	Weight	Runs
6.32.141	Validate mobile LCP < 2.5s under CPU throttling	<2.5s	Heavy	Deterministic
6.32.142	Validate layout stable on low-memory devices	Stable	Heavy	Deterministic
6.32.143	Validate JS execution < 1s on low-power mode	<1s	Heavy	Deterministic
6.32.144	Validate image decode time low on weak CPUs	Low	Medium	Deterministic
6.32.145	Validate fonts still load gracefully under slow networks	Graceful	Medium	Deterministic
6.32.146	Validate no memory leaks on mobile Safari	None	Medium	Deterministic
6.32.147	Validate reduced-motion mode improves rendering	Improved	Medium	Deterministic
6.32.148	Validate CPU-heavy components lazy-loaded	Lazy	Medium	Deterministic
6.32.149	Validate battery-saver mode does not break UX	Stable	Medium	Deterministic
6.32.150	Compute partial Performance score for Chunk 3	Complete	Critical	Deterministic

Rendering Diagnostics — Browser Compatibility & Interop

ID	Check	Passes when	Weight	Runs
6.32.151	Validate compatibility across major browsers (Chrome, Safari, Firefox, Edge)	Compatible	Heavy	Deterministic
6.32.152	Validate mobile Safari rendering cost minimized	Optimized	Heavy	Deterministic
6.32.153	Validate no legacy polyfills blocking rendering	Clean	Heavy	Deterministic
6.32.154	Validate WebView compatibility	Compatible	Medium	Deterministic
6.32.155	Validate no deprecated APIs in use	Clean	Medium	Deterministic
6.32.156	Validate shadow DOM complexity not excessive	Balanced	Medium	Deterministic
6.32.157	Validate no browser-specific layout shifts	None	Medium	Deterministic
6.32.158	Validate PWAs render consistently offline	Consistent	Medium	Deterministic
6.32.159	Validate responsiveness maintained under zoom	Stable	Medium	Deterministic
6.32.160	Validate reduced compute mode compatible across browsers	Compatible	Medium	Deterministic

Network Waterfall — Prioritization, Bundles, Parallelization

ID	Check	Passes when	Weight	Runs
6.32.161	Validate high‑priority resources delivered first	Optimal	Heavy	Deterministic
6.32.162	Validate JS bundles parallelized correctly	Parallel	Heavy	Deterministic
6.32.163	Validate CSS loads before JS for stability	Correct	Heavy	Deterministic
6.32.164	Validate image decode time optimized via modern codecs	Fast	Heavy	Deterministic
6.32.165	Validate minimal duplicate HTTP requests	Minimal	Medium	Deterministic
6.32.166	Validate streaming responses used where possible	Enabled	Medium	Deterministic
6.32.167	Validate inline scripts minimized	Minimal	Medium	Deterministic
6.32.168	Validate no blocking synchronous XHR	None	Medium	Deterministic
6.32.169	Validate no large JSON payloads > 200KB	Lean	Medium	Deterministic
6.32.170	Validate waterfall fully compressed (gzip/br)	Compressed	Medium	Deterministic

AI-Context Speed Signaling — Semantic Fast-Paths

ID	Check	Passes when	Weight	Runs
6.32.171	Validate semantic HTML delivered before JS	Early	Heavy	Deterministic
6.32.172	Validate structured data loads immediately	Immediate	Heavy	Deterministic
6.32.173	Validate AI can resolve site without heavy interactivity	Accessible	Heavy	Deterministic
6.32.174	Validate text-first rendering strategy implemented	Enabled	Medium	Deterministic
6.32.175	Validate minimal script execution required to read content	Minimal	Medium	Deterministic
6.32.176	Validate metadata readable in first 50ms	Fast	Medium	Deterministic
6.32.177	Validate AI-accessible snapshots available (SSR/ISR)	Available	Medium	Deterministic
6.32.178	Validate crawling speed consistent across pages	Consistent	Medium	Deterministic
6.32.179	Validate critical language tokens visible without JS	Visible	Medium	Deterministic
6.32.180	Validate hints for AI (priority sitemaps, clean cluster metadata)	Present	Medium	Deterministic

Final Performance Validations — Holistic System Check

ID	Check	Passes when	Weight	Runs
6.32.181	Validate performance consistent across 10 random URLs	Consistent	Heavy	Deterministic
6.32.182	Validate no regressions after simulated deploy	None	Heavy	Deterministic
6.32.183	Validate all rendering metrics stable (LCP, CLS, INP)	Stable	Heavy	Deterministic
6.32.184	Validate performance in low-network test (<1Mbps)	Acceptable	Heavy	Deterministic
6.32.185	Validate consistent preloading across pages	Consistent	Medium	Deterministic
6.32.186	Validate no blocked render cycles on mobile	Clean	Medium	Deterministic
6.32.187	Validate performance does not degrade in heavy UI states	Stable	Medium	Deterministic
6.32.188	Validate site remains functional even with JS disabled	Functional	Medium	Deterministic
6.32.189	Validate PWA installability unaffected by performance	Unaffected	Medium	Deterministic
6.32.190	Validate critical routes cached at edge for instant loads	Cached	Medium	Deterministic

Section 6.32 Performance Composite Scoring — Final Wrap

ID	Check	Passes when	Weight	Runs
6.32.191	Validate total site-wide performance score > 90%	>90%	Critical	Deterministic
6.32.192	Validate AI-speed signal score > 85%	>85%	Critical	Deterministic
6.32.193	Validate real-user performance (CrUX) aligns with lab data	Aligned	Heavy	Deterministic
6.32.194	Validate no regressions in functional flows under stress	None	Heavy	Deterministic
6.32.195	Validate asset pipelines optimized end-to-end	Optimized	Heavy	Deterministic
6.32.196	Validate server logs show no performance anomalies	Clean	Medium	Deterministic
6.32.197	Validate crawl budget efficiency >= 80%	>=80%	Medium	Deterministic
6.32.198	Validate all performance tests reproducible	Reproducible	Medium	Deterministic
6.32.199	Validate site-grade performance maintained over 30 days	Maintained	Medium	Deterministic
6.32.200	Compute full PERFORMANCE composite score	Finalized	Critical	Deterministic

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