12daysofweb.dev
Ranks Overall #527 Built Awesome #431
Data from Sep 10, 2026, 9:27 PM UTC old Measured once a week · 4 runs since Aug 20, 2026
Elsewhere:
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Wayback Machine
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Lighthouse Scores
Metrics Lighthouse, mobile
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 Lighthouse | ||
|---|---|---|---|
| Value | Change / range | Trend | |
| LCP CWV (estimate) Largest Contentful Paint | 1.56 s good | ↓ -50 ms (-3.1%) 1.55 s – 1.61 s | |
| INP CWV Interaction to Next Paint — field only, no lab run can measure it | n/a | — | |
| CLS CWV (estimate) Cumulative Layout Shift | 0 good | → no change 0 – 0 | |
| TBT Total Blocking Time | 4 ms good | ↑ +4 ms 0 ms – 5 ms | |
| FCP First Contentful Paint | 803 ms good | ↓ -16 ms (-2%) 803 ms – 819 ms | |
| Speed Index | 803 ms good | ↓ -16 ms (-2%) 803 ms – 819 ms | |
| TTFB Time to First Byte | 605 ms good | ↓ -23 ms (-3.7%) 604 ms – 628 ms | |
LCP Subparts lab observed, unthrottled
The subparts attribute LCP to your server, resource discovery, download, or rendering. Note that the Lab LCP shown above is throttled.
Page weight
| Metric | Value | Change / range | Trend |
|---|---|---|---|
| Page Weight | 54.1 kB | ↓ -234 B (-0.4%) 54.0 kB – 54.3 kB | |
| Requests | 13 | → no change 13 – 13 | |
| Third-party Weight | 2.7 kB | ↑ +1 B 2.7 kB – 2.7 kB | |
| Third-party CPU | 4 ms | → no change 2 ms – 4 ms | |
| Unused JS | 0 B | → no change 0 B – 0 B | |
| Unused CSS | 0 B | → no change 0 B – 0 B |
By resource type
- font 38.2% 20.6 kB · 1 req
- other 34.1% 18.5 kB · 2 req
- script 12.3% 6.6 kB · 7 req
- stylesheet 11.5% 6.2 kB · 1 req
- document 3.9% 2.1 kB · 1 req
Third parties 1 entities
2.7 kB transferred, 4 ms on the main thread.
Without JavaScript
The same load, photographed twice at 412×823: once with scripts disabled, once as rendered.
4.7% of pixels differ — they are nearly identical. 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 | 353 ms | ↑ +39 ms (+12.3%) 314 ms – 353 ms | |
| Long Tasks | 1 | ↑ +1 0 – 1 | |
| DOM Elements | 158 | → no change 158 – 158 | |
| Axe Violations Violating nodes from a full Axe CLI run (more than Lighthouse reports) | 1 | → no change 1 – 1 | |
| A11y Failures | 0 | → no change 0 – 0 | |
| A11y Failing Nodes | 0 | → no change 0 – 0 |
Main thread work
Axe violations axe-core 4.13.0, full rule set
1 violating node across 1 rule, 231 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 1 node
Hygiene
Measurement log
Field history 25 weeks
Weekly p75 from the CrUX History API, backfilled in a single request.
| Week ending | LCP | INP | CLS | FCP | TTFB |
|---|---|---|---|---|---|
| 2026-03-21 → 2026-09-05 | No data — 25 weeks under the CrUX reporting threshold | ||||
Runs
Every stored run for this URL, newest first.
| When | Scores | Perf | LCP | CLS | TBT | Weight | Runs | Spread | Bench | Took | Archive |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Sep 10, 2026, 9:27 PM UTC | 100 | 1.56 s | 0 | 4 ms | 54.1 kB | 3/3 | ±1 | 2,452 -1% | 21.6s |
|
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| Sep 3, 2026, 7:18 PM UTC | 100 | 1.61 s | 0 | 0 ms | 54.3 kB | 3/3 | ±5 | 2,491 0% | 24.6s |
|
|
| Aug 27, 2026, 4:08 PM UTC | 100 | 1.55 s | 0 | 0 ms | 54.0 kB | 3/3 | ±3 | 2,488 0% | 23.2s |
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| Aug 20, 2026, 3:36 PM UTC | 100 | 1.58 s | 0 | 5 ms | 54.3 kB | 3/3 | ±3 | 2,294 -8% | 22.8s |
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