speedlify2

Lighthouse lab metrics and Chrome UX Report field data for a list of sites, recorded on every run and compared over time.

Measurement runs · Embed a score · Field data from the Chrome UX Report ·

istanbul.js.org

https://istanbul.js.org/

79 84 96 100 –CWV 12AXE

Data from Aug 21, 2026, 1:15 AM UTC — 17h old.

Test Runners · 1 measurement · since Aug 21, 2026 · last attempt 17h

Stack

Detected on the same page load as the accessibility pass — the generator from <meta name="generator"> or the shape of the page, the host from response headers.

Ph Built with Phenomic 0.16.2
GitHub Pages Hosted by GitHub Pages

Scores

79
Performance
no change
84
Accessibility
no change
96
Best Practices
no change
100
SEO
no change

Lab metrics Lighthouse, mobile

Metric Current Previous Change Best Worst Trend
LCP Largest Contentful Paint 4.95 s — — 4.95 s 4.95 s
CLS Cumulative Layout Shift 0.052 — — 0.052 0.052
TBT Total Blocking Time 94 ms — — 94 ms 94 ms
FCP First Contentful Paint 1.69 s — — 1.69 s 1.69 s
Speed Index 3.41 s — — 3.41 s 3.41 s
TTFB Time to First Byte 759 ms — — 759 ms 759 ms

What LCP is made of

A flat LCP number tells you something regressed. The subparts tell you whether it was the server, resource discovery, the download, or rendering.

element render delay 1.14 s
time to first byte 270 ms

Page weight

Metric Current Previous Change Best Worst Trend
Page Weight 575.6 kB — — 575.6 kB 575.6 kB
Requests 12 — — 12 12
Third-party Weight 0 B — — 0 B 0 B
Third-party CPU 0 ms — — 0 ms 0 ms
Unused JS 66.4 kB — — 66.4 kB 66.4 kB
Unused CSS 0 B — — 0 B 0 B

By resource type

script 329.5 kB · 4 req
image 230.2 kB · 3 req
document 9.3 kB · 2 req
stylesheet 1.6 kB · 1 req
third party 6.2 kB · 4 req

Page health

Metric Current Previous Change Best Worst Trend
Main Thread Work 519 ms — — 519 ms 519 ms
Long Tasks 1 — — 1 1
DOM Elements 68 — — 68 68
Axe Violations Violating nodes from a full axe run — stricter than Lighthouse's subset 12 — — 12 12
A11y Failures 3 — — 3 3
A11y Failing Nodes 10 — — 10 10

Main thread work

script evaluation 221 ms
other 105 ms
script parse compile 91 ms
style layout 83 ms
parse HTML 11 ms
paint composite render 8 ms

Axe violations axe-core 4.13.0, full rule set

12 violating nodes across 4 rules, 166 passing. This is a standalone axe run, stricter than the subset Lighthouse folds into its score above — and it is the second tiebreaker in the ranking.

  • serious color-contrast — Elements must meet minimum color contrast ratio thresholds 8 nodes
  • moderate landmark-one-main — Document should have one main landmark 2 nodes
  • serious frame-title — Frames must have an accessible name 1 node
  • moderate region — All page content should be contained by landmarks 1 node

Accessibility failures 3 of 15 audits

Tracked as a count, not just the score — the weighted score is coarse enough that you can ship a broken component and barely move it.

  • color-contrast — Background and foreground colors do not have a sufficient contrast ratio. 8 nodes
  • frame-title — `<frame>` or `<iframe>` elements do not have a title 1 node
  • landmark-one-main — Document does not have a main landmark. 1 node

Hygiene

Changes rarely — which is exactly why a change is worth noticing.

HTTPS HSTS CSP Clickjacking protection Origin isolation Trusted Types bfcache h2 3 console errors

Measurement log

Every stored run for this URL, newest first. Failures are kept as records — "this site was down on Tuesday" is data too.

When PerfLCPCLSTBTWeight RunsSpreadBenchTook
Aug 21, 2026, 1:15 AM UTC 79 4.95 s 0.052 94 ms 575.6 kB 3/3 ±19 2,490 26.3s

Embed this score

Live below, then the markup that produces it. Drop that on any page to show istanbul.js.org's scores, updated whenever this instance re-measures — more about the component. Don’t forget to bundle the speedlify-score.js component code into your site! 

<speedlify-score speedlify-url="https://zachleat.github.io/speedlify2/" url="https://istanbul.js.org/"></speedlify-score>