The State of Web Vitals

Lab paint timeline

Lab paint timeline on a cold crawl: TTFB, FCP, LCP in ms - setup-specific, not field data.

Field data PhoneDesktopAll Scope All sites Q2 2026 edition · Phone field outcomes
Metric LCP INP CLS
1

At a glance the headline numbers for Lab paint timeline

Lab paint timeline on a cold crawl: TTFB, FCP, LCP in ms - setup-specific, not field data.

114ms
lab TTFB
on the typical page
366ms
lab FCP
on the typical page
556ms
lab LCP
on the typical page
185,348
sites measured
phone field data

In the lab, the typical site paints its main content after 556ms.

The State of Web Vitals · Q2 2026 · 189,915 sites · phone field datacorewebvitals.io/state-of-cwv
2

Distribution & median CLS site count and median CLS at each level of lab paint timeline — ttfb

0.00 0.04 0.08 0.11 0.15
0.1
0 43247 86494
0–99 100–199 200–299 300–399 400–499 500–599 600–699 700–799 800–899 900–999 1000+
Good (≤0.1) Needs improvement Poor (>0.25) Site count
The State of Web Vitals · Q2 2026 · 189,915 sites · phone field datacorewebvitals.io/state-of-cwv
3

Passing CLS by lab paint timeline — ttfb which level passes the CLS most often

Lab paint timeline — ttfbSitesPassing CLSCLS
0–99 86,494 88% 0.00
100–199 27,580 89% 0.00
200–299 14,515 90% 0.00
300–399 10,443 90% 0.00
400–499 7,871 90% 0.00
500–599 6,194 89% 0.00
600–699 4,941 91% 0.00
700–799 3,939 90% 0.00
800–899 3,253 88% 0.00
900–999 2,666 89% 0.00
1000+ 17,452 89% 0.00
Good Needs Improvement Poor Faded rows: under 100 sites

Lab paint timeline — ttfb 114ms. p75 399ms. p99 3.4s. At the low end (0–99ms): CLS 0.00. At the high end (1000+ms): CLS 0.00. computed

The State of Web Vitals · Q2 2026 · 189,915 sites · phone field datacorewebvitals.io/state-of-cwv
4

Distribution & median CLS site count and median CLS at each level of lab paint timeline — fcp

0.00 0.04 0.08 0.11 0.15
0.1
0 30210 60420
0–249 250–499 500–749 750–999 1000–1249 1250–1499 1500–1749 1750+
Good (≤0.1) Needs improvement Poor (>0.25) Site count
The State of Web Vitals · Q2 2026 · 189,915 sites · phone field datacorewebvitals.io/state-of-cwv
5

Passing CLS by lab paint timeline — fcp which level passes the CLS most often

Lab paint timeline — fcpSitesPassing CLSCLS
0–249 60,420 91% 0.00
250–499 52,470 89% 0.00
500–749 23,166 88% 0.00
750–999 13,077 88% 0.00
1000–1249 8,650 87% 0.00
1250–1499 5,799 87% 0.00
1500–1749 4,011 88% 0.00
1750+ 16,127 87% 0.00
Good Needs Improvement Poor Faded rows: under 100 sites

Lab paint timeline — fcp 366ms. p75 776ms. p99 10.2s. At the low end (0–249ms): CLS 0.00. At the high end (1750+ms): CLS 0.00. computed

The State of Web Vitals · Q2 2026 · 189,915 sites · phone field datacorewebvitals.io/state-of-cwv
6

Distribution & median CLS site count and median CLS at each level of lab paint timeline — lcp

0.00 0.04 0.08 0.11 0.15
0.1
0 40835 81670
0–499 500–999 1000–1499 1500–1999 2000–2499 2500–2999 3000–3499 3500–3999 4000–4499 4500+
Good (≤0.1) Needs improvement Poor (>0.25) Site count
The State of Web Vitals · Q2 2026 · 189,915 sites · phone field datacorewebvitals.io/state-of-cwv
7

Passing CLS by lab paint timeline — lcp which level passes the CLS most often

Lab paint timeline — lcpSitesPassing CLSCLS
0–499 81,670 91% 0.00
500–999 37,049 88% 0.00
1000–1499 16,429 86% 0.00
1500–1999 8,795 85% 0.00
2000–2499 5,047 86% 0.00
2500–2999 3,067 85% 0.00
3000–3499 2,832 86% 0.00
3500–3999 3,214 87% 0.00
4000–4499 3,290 87% 0.00
4500+ 14,786 86% 0.00
Good Needs Improvement Poor Faded rows: under 100 sites

Lab paint timeline — lcp 556ms. p75 1.4s. p99 19.3s. At the low end (0–499ms): CLS 0.00. At the high end (4500+ms): CLS 0.00. computed

The State of Web Vitals · Q2 2026 · 189,915 sites · phone field datacorewebvitals.io/state-of-cwv
8

Why this matters for the Core Web Vitals, and where to start fixing it

These are lab numbers from our crawler: one cold load, one machine, one network profile. They are not what your visitors feel. That is what the field data on the rest of this site measures. What the lab gives you is a controlled comparison: identical conditions for every site, so a difference between two sites is a real difference between the pages.

Read the gaps. Lab LCP far worse than field LCP usually means caching and repeat visits carry the field numbers. The reverse usually means the crawler's connection is kinder than your visitors' phones.

How does this affect the Core Web Vitals?

Lab paint timeline correlates with the CLS. Lab LCP separates passing sites from failing sites the most. Where the lab LCP is low, 91% of sites pass the CLS. Where it is high, 86% do. The decline is gradual. There is no point where sites suddenly start failing.

Go fix it How we measured → Chrome DevTools network settings for CWV testing →
Related signals Total Blocking Time (lab) → Main-thread CPU (lab) → Document lifecycle (lab) → Chrome field data from 189,915 sites, representing millions of real page loads · How we measured