Clerk.io vs Kiwi Sizing
Head-to-head usage across the sites we track.
Top sites by authority
Clerk.io · Kiwi Sizing · how many of each technology's sites sit in the web's highest authority tiers
Open Page Rank 9+
2
3
Open Page Rank 8+
2
4
Open Page Rank 7+
7
12
Open Page Rank 6+
12
23
Open Page Rank 5+
32
40
Open Page Rank scores 0 to 10 from the open web link graph; 9+ covers only a few hundred domains worldwide.
By country
Clerk.io · Kiwi Sizing · share of sites in each country using one or the other
United States
266
2,106
United Kingdom
418
952
India
121
962
Germany
453
620
Italy
518
490
France
304
590
Canada
103
787
Australia
79
688
Audience countries from the Chrome UX Report, top markets of either technology.
Real user performance
| Metric | Clerk.io | Kiwi Sizing |
|---|---|---|
| LCP | 1.7 s | 1.7 s |
| INP | 100 ms | 100 ms |
| CLS | 0 | 0 |
| TTFB | 700 ms | 500 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.