design-guide.publishing.service.gov.uk
https://design-guide.publishing.service.gov.uk/
Ranks Overall #1,025 Built Awesome #797
Data from Sep 14, 2026, 11:57 AM UTC old Measured once a week · 5 runs since Aug 20, 2026
Elsewhere:
PageSpeed Insights ·
Calibre ·
Treo ·
CrUX Vis ·
Scoring Calculator ·
Wayback Machine
Lab data is measured using Lighthouse, Mobile mode unless otherwise specified. Field data is reported from Chrome UX Report (using p75 measurements).
Stack
Lighthouse Scores LAB Simulated
Metrics LAB
No field data: the Chrome UX Report is not being collected for this project, so every figure below is from the Lighthouse run.
| Metric | Lab Simulated | ||
|---|---|---|---|
| Value | Change / range | Trend | |
| LCP CWV (estimate) Largest Contentful Paint | 1.51 s good | ↑ +12 ms (+0.8%) 1.50 s – 1.51 s | |
| INP CWV Interaction to Next Paint — field only, no lab run can measure it | n/a | — | |
| CLS CWV (estimate) Cumulative Layout Shift | 0.083 good | ↑ +0.083 0 – 0.083 | |
| TBT Total Blocking Time | 0 ms good | → no change 0 ms – 0 ms | |
| FCP First Contentful Paint | 1.22 s good | ↓ -288 ms (-19.2%) significant 1.22 s – 1.50 s | |
| Speed Index | 1.22 s good | ↓ -288 ms (-19.2%) significant 1.22 s – 1.50 s | |
| TTFB Time to First Byte | 615 ms good | ↑ +12 ms (+2%) 602 ms – 615 ms | |
LCP Subparts LAB Unthrottled
The subparts attribute LCP to your server, resource discovery, download, or rendering. Note that the Lab LCP shown above is a simulated throttled estimate.
Page weight
| Metric | Value | Change / range | Trend |
|---|---|---|---|
| Page Weight | 147 kB | ↑ +53 B 147 kB – 147 kB | |
| Requests | 9 | → no change 9 – 9 | |
| Third-party Weight | 0 B | → no change 0 B – 0 B | |
| Third-party CPU | 0 ms | → no change 0 ms – 0 ms | |
| Unused JS | 21.1 kB | → no change 21.1 kB – 21.1 kB | |
| Unused CSS | 19.8 kB | → no change 19.8 kB – 19.8 kB |
By resource type
| Type | Transfer | Share | Size | Requests |
|---|---|---|---|---|
| font | 44.9% | 65.2 kB | 2 | |
| script | 23.1% | 33.6 kB | 2 | |
| stylesheet | 14.9% | 21.6 kB | 1 | |
| image | 12.9% | 18.7 kB | 2 | |
| document | 4.2% | 6.1 kB | 1 | |
| Total | 147 kB | 9 |
Without JavaScript
The same load, photographed twice at 412×823: once with scripts disabled, once as rendered.
49.8% of pixels differ — parts of the page change. A shifted layout counts as difference, so a <noscript> banner alone can account for a large figure.
Page health
| Metric | Value | Change / range | Trend |
|---|---|---|---|
| Main Thread Work | 294 ms | ↑ +51 ms (+20.9%) significant 236 ms – 294 ms | |
| Long Tasks | 0 | → no change 0 – 0 | |
| DOM Elements | 146 | → no change 146 – 146 | |
| Axe Violations Violating nodes from a full Axe CLI run (more than Lighthouse reports) | 7 | → no change 7 – 7 | |
| A11y Failures | 0 | → no change 0 – 0 | |
| A11y Failing Nodes | 0 | → no change 0 – 0 |
Main thread work
| Task | Time | Share | Duration Simulated |
|---|---|---|---|
| other | 40% | 118 ms | |
| style layout | 26% | 76 ms | |
| script evaluation | 23% | 68 ms | |
| parse HTML | 6% | 19 ms | |
| paint composite render | 3% | 10 ms | |
| script parse compile | 1% | 2 ms | |
| Total | 294 ms |
Axe violations axe-core 4.13.0, full rule set
7 violating nodes across 6 rules, 252 passing. This is a standalone Axe CLI run and is stricter than the subset Lighthouse already includes.
-
moderate
landmark-unique— Landmarks should have a unique role or role/label/title (i.e. accessible name) combination 2 nodes -
moderate
landmark-banner-is-top-level— Banner landmark should not be contained in another landmark 1 node -
moderate
landmark-contentinfo-is-top-level— Contentinfo landmark should not be contained in another landmark 1 node -
moderate
landmark-no-duplicate-banner— Document should not have more than one banner landmark 1 node -
moderate
landmark-no-duplicate-contentinfo— Document should not have more than one contentinfo landmark 1 node -
moderate
region— All page content should be contained by landmarks 1 node
Hygiene
Measurement log
Every stored run for this URL, newest first.
| When | Scores | Perf | LCP | CLS | TBT | Weight | Runs | Spread | Bench | Took | Archive |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Sep 14, 2026, 11:57 AM UTC | 98 | 1.51 s | 0.083 | 0 ms | 147 kB | 3/3 | ±2 | 2,488 0% | 20.1s |
|
|
| Sep 7, 2026, 9:00 AM UTC | 100 | 1.50 s | 0 | 0 ms | 147 kB | 3/3 | ±2 | 2,492 0% | 21.2s |
|
|
| Aug 31, 2026, 3:55 AM UTC | 100 | 1.51 s | 0 | 0 ms | 147 kB | 3/3 | ±0 | 3,104 +25% | 20.5s |
|
|
| Aug 21, 2026, 2:38 PM UTC | 98 | 1.50 s | 0.083 | 0 ms | 147 kB | 3/3 | ±3 | 2,479 0% | 27.9s |
|
|
| Aug 20, 2026, 7:41 PM UTC | TRACING_ALREADY_STARTED: An internal Chrome error occurred. Please restart Chrome and try re-running Lighthouse. |
18.7s | |||||||||
Embed this score
Use this web component to show design-guide.publishing.service.gov.uk's scores on any website, updated whenever this instance re-measures. Don’t forget to bundle the speedlify2-score.js component code into your site!
<speedlify2-score speedlify-url="https://www.speedlify.dev/" url="https://design-guide.publishing.service.gov.uk/"></speedlify2-score>