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
15
Open Page Rank 8+
18
254
Open Page Rank 7+
68
1,096
Open Page Rank 6+
117
2,422
Open Page Rank 5+
181
4,597
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
27,194
United States
868
19,846
Germany
405
14,837
Italy
312
14,444
United Kingdom
489
12,352
Spain
346
10,837
India
564
10,040
Netherlands
321
8,273
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 | 1000 ms |
Median site's p75 values from the Chrome UX Report, Sep 2026. Lower is better; green meets Google's "good" threshold. This describes the sites that use each technology, not the technology's own overhead.