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 ·

github.com/lit/lit-element-starter-ts

https://github.com/lit/lit-element-starter-ts

45 97 96 100 ✗CWV 0AXE

Data from Aug 20, 2026, 11:27 PM UTC — 19h old.

Built Awesome · 1 measurement · since Aug 20, 2026 · last attempt 19h

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.

GitHub Pages Hosted by GitHub Pages

Core Web Vitals field data, origin-level

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

LCP 2.20 s good
INP 243 ms needs-improvement
CLS 0.020 good

Scores

45
Performance
no change
97
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 9.65 s — — 9.65 s 9.65 s
CLS Cumulative Layout Shift 0.002 — — 0.002 0.002
TBT Total Blocking Time 445 ms — — 445 ms 445 ms
FCP First Contentful Paint 8.90 s — — 8.90 s 8.90 s
Speed Index 8.90 s — — 8.90 s 8.90 s
TTFB Time to First Byte 604 ms — — 604 ms 604 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 360 ms
time to first byte 9 ms

Field data Chrome UX Report, origin-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 2.20 s good 80.6% good
INP CWV Interaction to Next Paint — field only, Lighthouse cannot measure this in a lab run 243 ms needs-improvement 70.3% good
CLS CWV 0.020 good 87.9% good
FCP 1.90 s needs-improvement 72% good
TTFB 1.17 s needs-improvement 46.4% good

Lab vs field

Lab LCP 9.65 s · field p75 2.20 s · real users are 0.23× 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 2.19 s 243 ms 0.020 1.89 s 1.17 s
2026-08-08 2.18 s 244 ms 0.020 1.87 s 1.17 s
2026-08-01 2.17 s 246 ms 0.020 1.85 s 1.17 s
2026-07-25 2.16 s 247 ms 0.020 1.84 s 1.16 s
2026-07-18 2.15 s 248 ms 0.030 1.85 s 1.17 s
2026-07-11 2.17 s 248 ms 0.030 1.86 s 1.18 s
2026-07-04 2.18 s 248 ms 0.030 1.87 s 1.20 s
2026-06-27 2.19 s 247 ms 0.030 1.88 s 1.22 s
2026-06-20 2.20 s 245 ms 0.020 1.88 s 1.23 s
2026-06-13 2.19 s 245 ms 0.020 1.87 s 1.24 s
2026-06-06 2.17 s 243 ms 0.020 1.86 s 1.24 s
2026-05-30 2.15 s 242 ms 0.020 1.85 s 1.23 s

Page weight

Metric Current Previous Change Best Worst Trend
Page Weight 1.81 MB — — 1.81 MB 1.81 MB
Requests 154 — — 154 154
Third-party Weight 1.66 MB — — 1.66 MB 1.66 MB
Third-party CPU 247 ms — — 247 ms 247 ms
Unused JS 373.4 kB — — 373.4 kB 373.4 kB
Unused CSS 178.5 kB — — 178.5 kB 178.5 kB

By resource type

script 1.36 MB · 104 req
stylesheet 288.9 kB · 22 req
other 61.1 kB · 14 req
document 51.3 kB · 1 req
image 48.2 kB · 13 req
third party 1.81 MB · 154 req

Third parties 1 entities

1.66 MB transferred, 247 ms of main thread time. This is the number most likely to regress without anyone on your team shipping anything.

githubassets.com 1.66 MB · 247 ms CPU

Page health

Metric Current Previous Change Best Worst Trend
Main Thread Work 5.70 s — — 5.70 s 5.70 s
Long Tasks 17 — — 17 17
DOM Elements 1,735 — — 1,735 1,735
Axe Violations Violating nodes from a full axe run — stricter than Lighthouse's subset 0 — — 0 0
A11y Failures 1 — — 1 1
A11y Failing Nodes 9 — — 9 9

Main thread work

script evaluation 1.87 s
style layout 1.86 s
other 1.56 s
parse HTML 225 ms
paint composite render 131 ms
garbage collection 38 ms
script parse compile 24 ms

Axe violations axe-core 4.13.0, full rule set

0 violating nodes across 0 rules, 2204 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.

Accessibility failures 1 of 32 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.

  • target-size — Touch targets do not have sufficient size or spacing. 9 nodes

Hygiene

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

HTTPS HSTS CSP Clickjacking protection Origin isolation Trusted Types bfcache h2 1 console error

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, 11:27 PM UTC 45 9.65 s 0.002 445 ms 1.81 MB 3/3 ±13 2,492 66.2s

Embed this score

Live below, then the markup that produces it. Drop that on any page to show github.com/lit/lit-element-starter-ts'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://github.com/lit/lit-element-starter-ts"></speedlify-score>