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https://barometer.thenationalconversation.org.uk

Performance

· 26 checks — Lighthouse + waterfall + sustainability rolled into one auditable list.
SCORE
95
GRADE
A
FIX
0
REVIEW
5
PASS
18
INFO
3

Performance-focused optimization plan with CWV assessment, top offenders, and time estimates

Mobile Desktop
56
Performance Overall performance score (0–100) based on Core Web Vitals and other metrics. 90+ is good.
100
Accessibility Measures how accessible the page is for users with disabilities. Checks color contrast, ARIA labels, and semantic HTML.
96
Best Practices Checks for modern web development best practices including HTTPS, no console errors, and secure JavaScript.
91
SEO Measures basic SEO optimizations: meta tags, crawlability, link text, and mobile friendliness.

First Contentful Paint First Contentful Paint — how long until the browser renders the first piece of content. Under 1.8s is good.

5.79 s

Largest Contentful Paint Largest Contentful Paint — how long until the largest visible element loads. Under 2.5s is good.

5.87 s

Total Blocking Time Total Blocking Time — total time the main thread was blocked, preventing user input. Under 200ms is good.

336 ms

Cumulative Layout Shift Cumulative Layout Shift — measures visual stability. How much the page layout shifts during loading. Under 0.1 is good.

0.000

Speed Index Speed Index — how quickly content is visually displayed during load. Under 3.4s is good.

5.79 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.

6.30 s

Page Load Progression

375 ms
750 ms
1.1 s
1.5 s
1.9 s
2.2 s
2.6 s
3.0 s
Checks
26
18 PASS 5 REVIEW
C
JS Execution Cost
Action
1472ms total JS execution
REVIEW
1472ms total JS execution
Warning::
https://barometer.thenationalconversation.org.uk/: 1053ms CPU time
Warning::
Unattributable: 367ms CPU time
Info::
https://barometer.thenationalconversation.org.uk/....: 51ms CPU time

Main Thread Breakdown

Other 33% Style & Layout 33% Parse HTML & CSS 21% Script Evaluation 8% Script Parsing & Compilation 4%
ScriptTotalScriptingParse/CompileParty
https://barometer.thenationalconversation.org.uk/1053ms61ms58ms1st
Unattributable367ms10ms0ms1st
https://barometer.thenationalconversation.org.uk/.netlify/scripts/rum51ms39ms2ms1st
B
HTTP/3 (QUIC)
HTTP/3 not advertised
REVIEW
HTTP/3 not advertised
Info::
HTTP/3 (QUIC) is not advertised
HTTP/3 isn't advertised via Alt-Svc and the worker didn't negotiate h3. HTTP/3 reduces handshake latency (1-RTT instead of 2-3 RTTs) and is more resilient on lossy connections. Most modern CDNs (Cloudflare, Fastly, AWS CloudFront, Google Cloud CDN) support HTTP/3 with a single config switch -- consider enabling for mobile-heavy workloads.
B
Server-Timing Observability
No Server-Timing header found
REVIEW
No Server-Timing header found
Info::
No Server-Timing header found
Server-Timing exposes backend timing breakdowns to browser DevTools (e.g., `db: 45ms; render: 120ms; cache: 2ms`). Useful for diagnosing slow pages without backend log access. Most modern frameworks (Next.js, Cloudflare Workers, Fastly) emit it automatically; absence on a managed platform usually means telemetry headers are stripped at the edge.
C
Green Hosting
Action
Whether the site is served from green-energy infrastructure
REVIEW

Green Hosting

No green hosting detected

B
HTTP Caching
public,max-age=0,must-revalidate
REVIEW
public,max-age=0,must-revalidate
Info::
Cache-Control header is set
Got: public,max-age=0,must-revalidate
Info::
ETag present — enables conditional (304) responses
Cache-Control

public,max-age=0,must-revalidate

DirectiveValueMeaning
public—Any cache may store this response
max-age0Cache for 0 seconds
must-revalidate—Must recheck with server after expiry
A
Page Weight Budget
1003 KB transferred, 11 requests
PASS
1003 KB transferred, 11 requests
Info::
Page weighs 1.9 MB (1003 KB transferred)
Info::
11 HTTP requests
Info::
Estimated 0.21 g CO2 per page load
1003 KB / 2.4 MB budget
1003 KB transferred
11 requests
0.21 g CO2 per page load
HTML 953.0 KiB 95%
Fonts 44.1 KiB 4%
JavaScript 4.2 KiB 0%
Other 1.3 KiB 0%
Images 0 B 0%
0 2.4 MB 4.9 MB
Under budget
A+
Third-Party Impact
4% third-party, 0 ms blocking
PASS
4% third-party, 0 ms blocking
Info::
Third-party code accounts for 4% of page weight (44.1 KiB of 1002.6 KiB)
Info::
Third-party blocking time is low (0 ms)
96%
First-party Third-party
A+
Text Compression
All text resources are compressed
PASS
All text resources are compressed
Info::
All text resources are compressed
All text resources are properly compressed.
A+
Image Optimization
4 images, 0 KB saveable
PASS
4 images, 0 KB saveable
Info::
All images are well-optimized
4 images 0 KB
0 oversized -0 KB
0 legacy format
0 missing dimensions CLS risk
A+
Font Loading
4 fonts (44 KB)
PASS
4 fonts (44 KB)
Info::
4 font(s) use font-display: swap (FOUT risk but functional)

Web fonts

4

44 KB total

Render-blocking

0

of 4

Dominant font-display

swap

Most common across fonts

Font loading timeline
Transfer FOIT (block) FOUT (swap)
0 ms 1.0 s 2.0 s 3.0 s 4.0 s 5.0 s 6.0 s FCP 5.8 s LCP 5.9 sdata:font/woff2;base64,d09GMgABAAAAACx4ABAAAAAAX1wAACwYAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAGoEsG5woHIVc…woff2;base64,d09GMgABAA... data:font/woff2;base64,d09GMgABAAAAACx4ABAAAAAAX1wAACwYAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAGoEsG5woHIVc… — 11.1 KiB — 173 ms — font-display: swapdata:font/woff2;base64,d09GMgABAAAAACyAABAAAAAAYFQAACwgAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAGoEsG5wiHIYG…woff2;base64,d09GMgABAA... data:font/woff2;base64,d09GMgABAAAAACyAABAAAAAAYFQAACwgAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAGoEsG5wiHIYG… — 11.1 KiB — 151 ms — font-display: swapdata:font/woff2;base64,d09GMgABAAAAACsQABAAAAAAYDQAACqtAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAGoEsG5wWHIYG…woff2;base64,d09GMgABAA... data:font/woff2;base64,d09GMgABAAAAACsQABAAAAAAYDQAACqtAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAGoEsG5wWHIYG… — 10.8 KiB — 152 ms — font-display: swapdata:font/woff2;base64,d09GMgABAAAAACxwABAAAAAAYAQAACwNAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAGoEsG5wcHIYG…woff2;base64,d09GMgABAA... data:font/woff2;base64,d09GMgABAAAAACxwABAAAAAAYAQAACwNAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAGoEsG5wcHIYG… — 11.1 KiB — 154 ms — font-display: swap
woff2;base64,d09GMgABAA... woff2 swap
Size 11 KB
Load time 173 ms
Start 234 ms
Risk FOUT — text flashes from fallback to web font
woff2;base64,d09GMgABAA... woff2 swap
Size 11 KB
Load time 151 ms
Start 259 ms
Risk FOUT — text flashes from fallback to web font
woff2;base64,d09GMgABAA... woff2 swap
Size 11 KB
Load time 152 ms
Start 259 ms
Risk FOUT — text flashes from fallback to web font
woff2;base64,d09GMgABAA... woff2 swap
Size 11 KB
Load time 154 ms
Start 260 ms
Risk FOUT — text flashes from fallback to web font
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)
A+
JS Bundles
1 scripts, 0 KB unused
PASS
1 scripts, 0 KB unused
0 KB unused JavaScript

Downloaded but never executed on this page.

ScriptSizeUnusedMinifiedParty
https://barometer.thenationalconversation.org.uk/.netlify/scripts/rum4 KB—✓1st
A+
Resource Caching
All resources properly cached
PASS
All resources properly cached
Info::
No caching issues found
All static resources have appropriate caching headers.
A+
Critical Rendering Path
No render-blocking resources
PASS
No render-blocking resources
Info::
No render-blocking resources detected
A+
Resource Hints
No optimization needed
PASS
No optimization needed
Info::
No resource hint issues
A+
Compression Algorithm
Main response uses brotli
PASS
Main response uses brotli
Info::
Main HTML response uses brotli (Content-Encoding: br)
Brotli is the best text-compression algorithm for general use, ~20% smaller than gzip on average (40% on smaller files). Modern browsers all support it.
A+
LCP Image Preload
LCP preload audit not available
PASS
LCP preload audit not available
Info::
LCP image preload audit not available for this scan
A+
Main HTML Cache-Control
Main HTML max-age=0 (≤ 5min) is appropriate
PASS
Main HTML max-age=0 (≤ 5min) is appropriate
Info::
Main HTML max-age=0 (≤ 5min) is appropriate
Got: public,max-age=0,must-revalidate
A+
Server Response Intelligence
3 server-response signal(s) detected
PASS
3 server-response signal(s) detected
Info::
`Cache-Status` header present (RFC 9211): "Netlify Edge"; hit; ttl=31526417
The page returns a `Cache-Status` header -- the standardized way for CDNs and caches to communicate per-hop cache state to debugging tools. Format: `Cache-Status: cdn-name; hit; ttl=300` (or `; fwd=miss` / `; fwd=stale`). Standard alternative to vendor-specific `X-Cache` patterns each CDN had historically. Cloudflare, Fastly, and Akamai all support emitting it.
Info::
`Vary` header declared: Accept-Encoding
The page declares a `Vary` header, telling downstream caches which request headers the response varies on. Critical for content-negotiated responses (compression, language, cookies, device class).
Info::
`ETag` present -- conditional GET supported
A+
Page Weight Inventory
11 resources · 1003 KB · 0 KB savings available
PASS
11 resources · 1003 KB · 0 KB savings available
Info::
Within 1MB page-weight target
Got: 1003 KB
Info::
8 third-party resources (4% of weight)
Info::
1 resources over 200KB
11 resources · 1002.6 KiB · 8 third-party Within 1MB page-weight target
Document 95% · 954.3 KiB
Font 4% · 44.1 KiB
JavaScript 0% · 4.2 KiB
Image 0% · 0 B
A+
Render-Blocking Resources
No render-blocking resources detected
PASS
No render-blocking resources detected
Info::
No render-blocking resources detected in <head>
A+
Third-Party Resources
No third-party resources detected
PASS
No third-party resources detected
A+
JavaScript Blocking
No render-blocking JS or document.write usage detected
PASS
No render-blocking JS or document.write usage detected
Info::
No JavaScript blocking issues detected
A+
CSS Performance Depth
No CSS performance depth issues detected
PASS
No CSS performance depth issues detected
Info::
No CSS performance depth issues detected
Network Waterfall
11 requests over 455ms
INFO
0 ms 1.0 s 2.0 s 3.0 s 4.0 s 5.0 s 6.0 s FCP 5.8 s LCP 5.9 shttps://barometer.thenationalconversation.org.uk// https://barometer.thenationalconversation.org.uk/ — 200 — 953.0 KiB — 158 ms — h2data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAB4AAAAQ4CAYAAADo08FDAACxzElEQVR4nOz9T4xk6d4n9H3PfQNmh…data:image/png;base64,iVBORw0KGgoAA... data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAB4AAAAQ4CAYAAADo08FDAACxzElEQVR4nOz9T4xk6d4n9H3PfQNmh… — 200 — 0 B — 2 ms — datadata:image/jpeg;base64,/9j/4AAQSkZJRgABAQAAAQABAAD/2wBDAA0JCgwKCA0MCwwPDg0QFCIWFBISFCkdHxgiMSszMjAr…data:image/jpeg;base64,/9j/4AAQSkZJ... data:image/jpeg;base64,/9j/4AAQSkZJRgABAQAAAQABAAD/2wBDAA0JCgwKCA0MCwwPDg0QFCIWFBISFCkdHxgiMSszMjAr… — 200 — 0 B — 3 ms — datadata:font/woff2;base64,d09GMgABAAAAACx4ABAAAAAAX1wAACwYAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAGoEsG5woHIVc…data:font/woff2;base64,d09GMgABAAAA... data:font/woff2;base64,d09GMgABAAAAACx4ABAAAAAAX1wAACwYAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAGoEsG5woHIVc… — 200 — 11.1 KiB — 173 ms — datadata:image/jpeg;base64,/9j/4AAQSkZJRgABAQAAAQABAAD/2wBDAA0JCgsKCA0LCgsODg0PEyAVExISEyccHhcgLikxMC4p…data:image/jpeg;base64,/9j/4AAQSkZJ... data:image/jpeg;base64,/9j/4AAQSkZJRgABAQAAAQABAAD/2wBDAA0JCgsKCA0LCgsODg0PEyAVExISEyccHhcgLikxMC4p… — 200 — 0 B — 5 ms — datadata:image/jpeg;base64,/9j/4AAQSkZJRgABAQAAAQABAAD/2wBDAAwICQsJCAwLCgsODQwOEh4UEhEREiUbHBYeLCcuLisn…data:image/jpeg;base64,/9j/4AAQSkZJ... data:image/jpeg;base64,/9j/4AAQSkZJRgABAQAAAQABAAD/2wBDAAwICQsJCAwLCgsODQwOEh4UEhEREiUbHBYeLCcuLisn… — 200 — 0 B — 7 ms — datadata:font/woff2;base64,d09GMgABAAAAACyAABAAAAAAYFQAACwgAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAGoEsG5wiHIYG…data:font/woff2;base64,d09GMgABAAAA... data:font/woff2;base64,d09GMgABAAAAACyAABAAAAAAYFQAACwgAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAGoEsG5wiHIYG… — 200 — 11.1 KiB — 151 ms — datadata:font/woff2;base64,d09GMgABAAAAACsQABAAAAAAYDQAACqtAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAGoEsG5wWHIYG…data:font/woff2;base64,d09GMgABAAAA... data:font/woff2;base64,d09GMgABAAAAACsQABAAAAAAYDQAACqtAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAGoEsG5wWHIYG… — 200 — 10.8 KiB — 152 ms — datadata:font/woff2;base64,d09GMgABAAAAACxwABAAAAAAYAQAACwNAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAGoEsG5wcHIYG…data:font/woff2;base64,d09GMgABAAAA... data:font/woff2;base64,d09GMgABAAAAACxwABAAAAAAYAQAACwNAAEAAAAAAAAAAAAAAAAAAAAAAAAAAAAAGoEsG5wcHIYG… — 200 — 11.1 KiB — 154 ms — datahttps://barometer.thenationalconversation.org.uk/.netlify/scripts/rum/.netlify/scripts/rum https://barometer.thenationalconversation.org.uk/.netlify/scripts/rum — 200 — 4.2 KiB — 15 ms — h2https://barometer.thenationalconversation.org.uk/favicon.ico/favicon.ico https://barometer.thenationalconversation.org.uk/favicon.ico — 404 — 1.3 KiB — 13 ms — h2
HTML JavaScript CSS Images Fonts XHR/Fetch Other
Real-User Performance (CrUX)
Field metrics from the Chrome User Experience Report
INFO

Chrome User Experience (CrUX)

Real-user metrics from the Chrome UX Report (2026-07-21 — 2026-08-17)

LCP (p75)

0 ms

0% good

INP (p75)

0 ms

0% good

CLS (p75)

0.000

0% good

FCP (p75)

1076 ms

TTFB (p75)

0 ms

Image Optimization
1 images, 0 KB total, 0 KB wasted
INFO

Image Optimization Audit

Total Images

1

Total Size

0 KB

Oversized

1

1 missing dimensions
All checks on this page are automated. Results are estimates - run targeted manual reviews when the score affects a release decision.

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