Customer.io vs Sendinblue
Head-to-head usage across the sites we track.
Top sites by authority
Customer.io · Sendinblue · how many of each technology's sites sit in the web's highest authority tiers
Open Page Rank 9+
1
13
Open Page Rank 8+
18
250
Open Page Rank 7+
72
1,100
Open Page Rank 6+
126
2,435
Open Page Rank 5+
192
4,621
Open Page Rank scores 0 to 10 from the open web link graph; 9+ covers only a few hundred domains worldwide.
By country
Customer.io · Sendinblue · share of sites in each country using one or the other
France
370
25,958
United States
883
19,918
Germany
422
14,883
Italy
315
13,878
United Kingdom
487
12,372
India
574
10,203
Spain
335
10,428
Netherlands
312
8,237
Audience countries from the Chrome UX Report, top markets of either technology.
Real user performance
| Metric | Customer.io | Sendinblue |
|---|---|---|
| LCP | 2.4 s | 2 s |
| INP | 125 ms | 75 ms |
| CLS | 0 | 0 |
| TTFB | 800 ms | 900 ms |
Median site's p75 values from the Chrome UX Report, Aug 2026. Lower is better; green meets Google's "good" threshold. This describes the sites that use each technology, not the technology's own overhead.