A/B testing impact

Performance impact by ab_testing provider.

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

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

Performance impact by ab_testing provider.

8
Providers ranked
After min-sites filter
21,106
Sites in sample
Combined across all items
125ms
Best INP (p75)
Google Optimize
The State of Web Vitals · Q2 2026 · 189,915 sites · phone field datacorewebvitals.io/state-of-cwv
2

The ranking sorted by INP at p75, fastest first

# Provider INP p75 Passing Sites
1 Google Optimize 125ms 93.5%
19,928
2 AB Tasty 194ms 75.6%
109
3 Convert 197ms 76.9%
191
4 VWO 204ms 73.5%
433
5 Optimizely 239ms 61.0%
137
6 Kameleoon 242ms 62.0%
112
7 LaunchDarkly 254ms 66.7%
131
8 Dynamic Yield 322ms 39.6%
65
The State of Web Vitals · Q2 2026 · 189,915 sites · phone field datacorewebvitals.io/state-of-cwv
3

Passing INP per provider which group passes the INP most often

ProviderSitesPassing INPp75
Google Optimize 10.5% 19,928 94% 125ms
Convert 0.1% 191 77% 197ms
AB Tasty 0.1% 109 76% 194ms
VWO 0.2% 433 74% 204ms
LaunchDarkly 0.1% 131 67% 254ms
Kameleoon 0.1% 112 62% 242ms
Optimizely 0.1% 137 61% 239ms
Split.io 0% 9 50% 283ms
Monetate 0% 26 45% 232ms
Dynamic Yield 0% 65 40% 322ms
Good Needs Improvement Poor Sorted best-passing first · median colored by its own rating · pass = good INP (200ms at p75) · one value per site

94% of Google Optimize sites pass INP. Optimizely trails 33 points behind, leaving 39% of its sites failing. computed

The State of Web Vitals · Q2 2026 · 189,915 sites · phone 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 10.5%
812.3s
94125ms
870.03
731.9s
541.3s
VWO 0.2%
762.4s
74204ms
830.05
692.0s
531.3s
Convert 0.1%
672.7s
77197ms
800.07
692.1s
511.5s
Optimizely 0.1%
682.9s
61239ms
780.09
612.2s
441.2s
LaunchDarkly 0.1%
454.1s
67254ms
710.13
453.0s
541.2s
Kameleoon 0.1%
772.4s
62242ms
770.07
701.9s
531.1s
AB Tasty 0.1%
782.2s
76194ms
720.12
731.8s
56927ms
Dynamic Yield 0%
662.7s
40322ms
640.21
711.9s
631.1s
Monetate 0%
782.4s
45232ms
780.06
701.9s
391.1s
Split.io 0%
573.2s
50283ms
430.20
432.6s
571.2s
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.

Google Optimize leads on INP: 94% of its sites pass. Optimizely trails at 61%. computed

The State of Web Vitals · Q2 2026 · 189,915 sites · phone field datacorewebvitals.io/state-of-cwv
Related signals Maps (4) → CDN (15) → Chat & messaging (17) → Bot detection (7) → Chrome field data from 189,915 sites, representing millions of real page loads · How we measured