A/B testing impact

Performance impact by ab_testing provider.

Field data PhoneDesktopAll Scope All sites Q1 2026 edition · Desktop field outcomes
Metric LCP INP CLS
1

At a glance the headline numbers for A/B testing impact

Performance impact by ab_testing provider.

7
Providers ranked
After min-sites filter
11,168
Sites in sample
Combined across all items
61ms
Best INP (p75)
Google Optimize
The State of Web Vitals · Q1 2026 · 94,910 sites · desktop field datacorewebvitals.io/state-of-cwv
2

The ranking sorted by INP at p75, fastest first

# Provider INP p75 Passing Sites
1 Google Optimize 61ms 99.2%
10,546
2 AB Tasty 95ms 97.7%
53
3 VWO 96ms 97.7%
246
4 Convert 101ms 100.0%
105
5 Kameleoon 117ms 94.4%
60
6 Optimizely 122ms 88.7%
82
7 LaunchDarkly 127ms 80.5%
76
The State of Web Vitals · Q1 2026 · 94,910 sites · desktop field datacorewebvitals.io/state-of-cwv
3

Passing INP per provider which group passes the INP most often

ProviderSitesPassing INPp75
Monetate 0% 13 100% 119ms
Convert 0.1% 105 100% 101ms
Google Optimize 11.1% 10,546 99% 61ms
VWO 0.3% 246 98% 96ms
AB Tasty 0.1% 53 98% 95ms
Kameleoon 0.1% 60 94% 117ms
Optimizely 0.1% 82 89% 122ms
Dynamic Yield 0% 37 82% 195ms
LaunchDarkly 0.1% 76 81% 127ms
Split.io 0% 5 67% 185ms
Good Needs Improvement Poor Sorted best-passing first · median colored by its own rating · pass = good INP (200ms at p75) · one value per site

No provider stands out: pass rates sit between 98% and 100%. computed

The State of Web Vitals · Q1 2026 · 94,910 sites · desktop field datacorewebvitals.io/state-of-cwv
4

All five vitals at once the whole category without toggling - cell is the pass rate, small number the p75

LCP
INP
CLS
FCP
TTFB
Google Optimize 11.1%
862.0s
9961ms
760.10
811.6s
591.2s
VWO 0.3%
802.3s
9896ms
790.09
771.7s
521.1s
Convert 0.1%
762.5s
100101ms
660.15
722.0s
601.5s
Optimizely 0.1%
702.8s
89122ms
680.15
731.9s
601.1s
LaunchDarkly 0.1%
553.5s
81127ms
640.23
582.7s
75786ms
Kameleoon 0.1%
842.0s
94117ms
800.09
861.6s
491.1s
AB Tasty 0.1%
772.1s
9895ms
640.15
801.5s
72815ms
Dynamic Yield 0%
702.7s
82195ms
600.19
671.9s
571.4s
Monetate 0%
852.1s
100119ms
850.06
851.7s
461.4s
Split.io 0%
672.7s
67185ms
330.43
671.6s
100324ms
60%95%+ passing Cell: pass rate, small number = p75 · faded rows: under 100 sites

One row per provider, one column per vital - the cell is the share of sites passing, the small number the p75. No toggling needed to see where the category actually differs.

Convert leads on INP: 100% of its sites pass. VWO trails at 98%. computed

The State of Web Vitals · Q1 2026 · 94,910 sites · desktop field datacorewebvitals.io/state-of-cwv
Related signals Maps (4) → CDN (15) → Chat & messaging (16) → Bot detection (7) → Chrome field data from 94,910 sites, representing millions of real page loads · How we measured