In the lab, the typical site paints its main content after 559ms

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.

120ms

lab TTFB

on the typical page

367ms

lab FCP

on the typical page

559ms

lab LCP

on the typical page

94,841

sites measured

phone field data

In the lab, the typical site paints its main content after 559ms.

The State of Web Vitals · Q1 2026 · 94,910 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 10957 21914

0 1–2 3–5 6–10 11–23 24–50 51–108 109–236 237–516 517–1126 1127–2458 >p98

Good (≤0.1) Needs improvement Poor (>0.25) Site count

The State of Web Vitals · Q1 2026 · 94,910 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 51 83% 0.00

1–2 106 86% 0.00

3–5 66 83% 0.00

6–10 37 74% 0.00

11–23 5,364 85% 0.00

24–50 21,914 88% 0.00

51–108 17,504 89% 0.00

109–236 15,564 90% 0.00

237–516 14,706 90% 0.00

517–1126 11,877 89% 0.00

1127–2458 5,757 89% 0.00

>p98 1,895 89% 0.00

Good Needs Improvement Poor Faded rows: under 100 sites

Lab paint timeline — ttfb 120ms. p75 413ms. p99 3.5s. At the low end (0ms): CLS 0.00. At the high end (>p98): CLS 0.00. computed

The State of Web Vitals · Q1 2026 · 94,910 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 9753 19505

55–85 86–131 132–203 204–313 314–483 484–746 747–1153 1154–1780 1781–2750 2751–4247 >p98

Good (≤0.1) Needs improvement Poor (>0.25) Site count

The State of Web Vitals · Q1 2026 · 94,910 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

55–85 506 92% 0.00

86–131 5,432 93% 0.00

132–203 15,117 91% 0.00

204–313 19,505 89% 0.00

314–483 16,208 89% 0.00

484–746 13,064 88% 0.00

747–1153 9,933 87% 0.00

1154–1780 6,830 88% 0.00

1781–2750 3,764 87% 0.00

2751–4247 1,763 87% 0.00

>p98 1,880 86% 0.00

Good Needs Improvement Poor Faded rows: under 100 sites

Lab paint timeline — fcp 367ms. p75 765ms. p99 5.7s. At the low end (55–85ms): CLS 0.00. At the high end (>p98): CLS 0.00. computed

The State of Web Vitals · Q1 2026 · 94,910 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 9623 19245

26–46 47–81 82–144 145–255 256–450 451–796 797–1409 1410–2491 2492–4407 4408–7795 >p98

Good (≤0.1) Needs improvement Poor (>0.25) Site count

The State of Web Vitals · Q1 2026 · 94,910 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

47–81 328 92% 0.00

82–144 4,472 93% 0.00

145–255 14,331 92% 0.00

256–450 19,245 91% 0.00

451–796 16,802 88% 0.00

797–1409 13,205 87% 0.00

1410–2491 8,327 85% 0.00

2492–4407 5,971 86% 0.00

4408–7795 5,639 86% 0.00

>p98 1,803 84% 0.00

Good Needs Improvement Poor Faded rows: under 100 sites

Lab paint timeline — lcp 559ms. p75 1.4s. p99 10.3s. At the low end (47–81ms): CLS 0.00. At the high end (>p98): CLS 0.00. computed

The State of Web Vitals · Q1 2026 · 94,910 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, 92% of sites pass the CLS. Where it is high, 84% 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 →