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 ·

developer.chrome.com

https://developer.chrome.com/

50 93 77 92 ✗CWV 23AXE

Data from Aug 20, 2026, 8:38 PM UTC — 22h old.

Built Awesome · 1 measurement · since Aug 20, 2026 · last attempt 22h

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.

Go Hosted by Google Frontend

Core Web Vitals field data, url-level

Real Chrome users, 28-day window (2026-07-22 → 2026-08-18). This is what Google measures you on.

LCP 3.04 s needs-improvement
INP 287 ms needs-improvement
CLS 0.020 good

Scores

50
Performance
no change
93
Accessibility
no change
77
Best Practices
no change
92
SEO
no change

Lab metrics Lighthouse, mobile

Metric Current Previous Change Best Worst Trend
LCP Largest Contentful Paint 7.03 s — — 7.03 s 7.03 s
CLS Cumulative Layout Shift 0.003 — — 0.003 0.003
TBT Total Blocking Time 1.00 s — — 1.00 s 1.00 s
FCP First Contentful Paint 2.81 s — — 2.81 s 2.81 s
Speed Index 2.93 s — — 2.93 s 2.93 s
TTFB Time to First Byte 801 ms — — 801 ms 801 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.

time to first byte 459 ms
element render delay 379 ms

Field data Chrome UX Report, url-level

Real Chrome users, 28-day trailing window (2026-07-22 → 2026-08-18). This is what Google measures you on.

Metric p75 Rating Distribution (good / needs work / poor)
LCP CWV 3.04 s needs-improvement 65.4% good
INP CWV Interaction to Next Paint — field only, Lighthouse cannot measure this in a lab run 287 ms needs-improvement 60.2% good
CLS CWV 0.020 good 87.4% good
FCP 2.98 s needs-improvement 45.8% good
TTFB 1.90 s poor 18.4% good

Lab vs field

Lab LCP 7.03 s · field p75 3.04 s · real users are 0.43× faster than the lab.

Field history 25 weeks

Weekly p75 from the CrUX History API, backfilled in a single request.

Week ending LCPINPCLSFCPTTFB
2026-08-15 3.01 s 284 ms 0.020 2.95 s 1.88 s
2026-08-08 3.02 s 281 ms 0.020 2.95 s 1.87 s
2026-08-01 2.99 s 279 ms 0.020 2.93 s 1.87 s
2026-07-25 3.00 s 284 ms 0.020 2.93 s 1.87 s
2026-07-18 2.98 s 287 ms 0.020 2.91 s 1.84 s
2026-07-11 2.99 s 290 ms 0.020 2.93 s 1.84 s
2026-07-04 3.02 s 292 ms 0.020 2.95 s 1.83 s
2026-06-27 2.99 s 294 ms 0.020 2.93 s 1.80 s
2026-06-20 2.99 s 294 ms 0.020 2.92 s 1.79 s
2026-06-13 2.96 s 294 ms 0.020 2.88 s 1.76 s
2026-06-06 2.92 s 291 ms 0.020 2.84 s 1.74 s
2026-05-30 2.90 s 287 ms 0.020 2.83 s 1.75 s

Page weight

Metric Current Previous Change Best Worst Trend
Page Weight 1.74 MB — — 1.74 MB 1.74 MB
Requests 68 — — 68 68
Third-party Weight 1.77 MB — — 1.77 MB 1.77 MB
Third-party CPU 442 ms — — 442 ms 442 ms
Unused JS 525.9 kB — — 525.9 kB 525.9 kB
Unused CSS 134.2 kB — — 134.2 kB 134.2 kB

By resource type

script 1.16 MB · 42 req
image 216.6 kB · 10 req
stylesheet 165.3 kB · 4 req
font 164.7 kB · 2 req
document 20.4 kB · 1 req
other 17.6 kB · 9 req
third party 1.49 MB · 56 req

Third parties 6 entities

1.77 MB transferred, 442 ms of main thread time. This is the number most likely to regress without anyone on your team shipping anything.

Google CDN 807.4 kB · 110 ms CPU
Google Tag Manager 771.1 kB · 329 ms CPU
Google Fonts 168.7 kB · 0 ms CPU
Unpkg 15.7 kB · 2 ms CPU
Google/Doubleclick Ads 7.9 kB · 1 ms CPU

Page health

Metric Current Previous Change Best Worst Trend
Main Thread Work 3.42 s — — 3.42 s 3.42 s
Long Tasks 11 — — 11 11
DOM Elements 828 — — 828 828
Axe Violations Violating nodes from a full axe run — stricter than Lighthouse's subset 23 — — 23 23
A11y Failures 2 — — 2 2
A11y Failing Nodes 22 — — 22 22

Main thread work

script evaluation 1.73 s
other 650 ms
style layout 480 ms
script parse compile 367 ms
paint composite render 110 ms
parse HTML 68 ms
garbage collection 17 ms

Axe violations axe-core 4.13.0, full rule set

23 violating nodes across 3 rules, 970 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 link-name — Links must have discernible text 20 nodes
  • serious color-contrast — Elements must meet minimum color contrast ratio thresholds 2 nodes
  • moderate page-has-heading-one — Page should contain a level-one heading 1 node

Accessibility failures 2 of 30 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.

  • link-name — Links do not have a discernible name 20 nodes
  • color-contrast — Background and foreground colors do not have a sufficient contrast ratio. 2 nodes

Hygiene

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

HTTPS HSTS CSP Clickjacking protection Origin isolation Trusted Types bfcache h2

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 20, 2026, 8:38 PM UTC 50 7.03 s 0.003 1.00 s 1.74 MB 3/3 ±3 2,337 48.9s

Embed this score

Live below, then the markup that produces it. Drop that on any page to show developer.chrome.com'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://developer.chrome.com/"></speedlify-score>