Email marketing impact React sites
Performance impact by email_marketing provider.
1
At a glance the headline numbers for Email marketing impact
Performance impact by email_marketing provider.
3
Providers ranked
After min-sites filter
290
Sites in sample
Combined across all items
3.0s
Best LCP (p75)
HubSpot
The State of Web Vitals · October 2026 · React sites (9,570) · desktop field datacorewebvitals.io/state-of-cwv
2
The ranking sorted by LCP at p75, fastest first
| # | Provider | LCP p75 | Passing | Sites | |
|---|---|---|---|---|---|
| 1 | HubSpot | 3.0s | 60.4% | 90 | |
| 2 | Klaviyo | 3.2s | 66.7% | 70 | |
| 3 | Mailchimp | 3.3s | 50.0% | 130 |
The State of Web Vitals · October 2026 · React sites (9,570) · desktop field datacorewebvitals.io/state-of-cwv
3
Passing LCP per provider which group passes the LCP most often
ProviderSitesPassing LCPp75
Salesforce Marketing Cloud 0.1% 8 1.7s
Klaviyo 0.7% 70 3.2s
HubSpot 0.9% 90 3.0s
ActiveCampaign 0.2% 15 2.6s
Mailchimp 1.4% 130 3.3s
Good Needs Improvement Poor Sorted best-passing first · median colored by its own rating · pass = good LCP (2.5s at p75) · one value per site
The State of Web Vitals · October 2026 · React sites (9,570) · 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
Mailchimp 1.4%
503.3s
10067ms
720.12
402.6s
232.4s
HubSpot 0.9%
603.0s
9680ms
690.17
572.5s
381.9s
Klaviyo 0.7%
673.2s
10076ms
800.08
672.2s
422.1s
ActiveCampaign 0.2%
602.6s
10099ms
700.13
402.3s
201.9s
Salesforce Marketing Cloud 0.1%
1001.7s
100151ms
380.20
1001.5s
100706ms
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.
The State of Web Vitals · October 2026 · React sites (9,570) · desktop field datacorewebvitals.io/state-of-cwv
Related signals Font services (4) → Session recording (11) → CMS (17) → Search (6) → 210,902 crawled sites with Chrome field data, representing millions of real page loads · How we measured
210,902 crawled sites with Chrome field data, representing millions of real page loads. How we measured.