Performance
· 22 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.Performance-focused optimization plan with CWV assessment, top offenders, and time estimates
First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.
958 ms
Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.
3.17 s
Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.
0 ms
Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.
0.550
Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.
1.13 s
Time to Interactive Time to Interactive — how long until the page is fully interactive and responds to user input. Under 3.8s is good.
3.20 s
Page Load Progression
FPage Weight BudgetAction3.8 MB transferred, 37 requestsFIX
Convert images to WebP/AVIF and resize to display dimensions to reduce transfer size.
Image bandwidth is high — modern formats (WebP/AVIF) and resizing typically cut it 50%+.
Source: web.dev
DThird-Party ImpactAction98% third-party, 0 ms blockingFIX
DPage Weight InventoryAction37 resources · 3.8 MB · 0 KB savings availableFIX
| # | Resource | Type | Size | Cache | Unused | 3rd party | Issues |
|---|---|---|---|---|---|---|---|
| — | — | ||||||
| 37 resources | 3.8 MiB | ||||||
BImage Optimization27 images, 0 KB saveableREVIEW
CJS Execution CostAction1071ms total JS executionREVIEW
Main Thread Breakdown
| Script | Total | Scripting | Parse/Compile | Party |
|---|---|---|---|---|
| https://though-threatened-trains-station.trycloudflare.com/ | 892ms | 25ms | 2ms | 1st |
| Unattributable | 179ms | 3ms | 0ms | 1st |
BHTTP/3 (QUIC)HTTP/3 not advertisedREVIEW
BCompression AlgorithmMain response uses gzip; brotli would be ~20% smallerREVIEW
BServer-Timing ObservabilityNo Server-Timing header foundREVIEW
A+Text CompressionAll text resources are compressedPASS
A+Font Loading3 fonts (184 KB)PASS
Web fonts
3
184 KB total
Render-blocking
0
of 3
Dominant font-display
swap
Most common across fonts
Font loading timeline
- Subset this font — over 100 KB suggests Latin Extended or full glyph coverage that most pages don't need
Optimization checklist
- Preload critical fonts (priority=high)
- Use woff2 format for all fonts
- Set font-display to swap, optional, or fallback
- Subset large fonts (≤100 KB each)
Fixing the unchecked items could save ~77 KB and ~154 ms
A+JS Bundles1 scripts, 0 KB unusedPASS
Downloaded but never executed on this page.
| Script | Size | Unused | Minified | Party |
|---|---|---|---|---|
| https://though-threatened-trains-station.trycloudflare.com/env-config.js | 0 KB | — | ✓ | 1st |
A+Resource CachingAll resources properly cachedPASS
A+Critical Rendering PathNo render-blocking resourcesPASS
A+Resource HintsNo optimization neededPASS
A+LCP Image PreloadLCP preload audit not availablePASS
A+Main HTML Cache-ControlMain HTML max-age=10 (≤ 5min) is appropriatePASS
A+Server Response Intelligence2 server-response signal(s) detectedPASS
A+Green HostingWhether the site is served from green-energy infrastructurePASS
Green Hosting
This site is hosted on green energy infrastructure
Provider: Cloudflare
AHTTP Cachingmax-age=10 (10 seconds)PASS
public, max-age=10, must-revalidate
| Directive | Value | Meaning |
|---|---|---|
| public | — | Any cache may store this response |
| max-age | 10 | Cache for 10 seconds |
| must-revalidate | — | Must recheck with server after expiry |
Network Waterfall37 requests over 988msINFO
Real-User Performance (CrUX)Field metrics from the Chrome User Experience ReportINFO
Chrome User Experience (CrUX)
Real-user metrics from the Chrome UX Report (2026-06-29 — 2026-07-26)
LCP (p75)
3092 ms
65% good
INP (p75)
197 ms
75% good
CLS (p75)
0.230
73% good
FCP (p75)
2009 ms
TTFB (p75)
1606 ms
Image Optimization34 images, 0 KB total, 0 KB wastedINFO
Image Optimization Audit
Total Images
34
Total Size
0 KB
Oversized
26