Optimizely vs SiteSpect
Head-to-head usage across the sites we track.
Top sites by authority
Optimizely · SiteSpect · how many of each technology's sites sit in the web's highest authority tiers
Open Page Rank 9+
31
0
Open Page Rank 8+
401
4
Open Page Rank 7+
1,141
6
Open Page Rank 6+
1,788
12
Open Page Rank 5+
2,572
18
Open Page Rank scores 0 to 10 from the open web link graph; 9+ covers only a few hundred domains worldwide.
By country
Optimizely · SiteSpect · share of sites in each country using one or the other
United States
25,512
825
Canada
6,167
138
India
4,899
59
United Kingdom
4,567
59
Australia
4,029
39
Germany
3,412
52
France
3,284
53
Spain
3,112
50
Audience countries from the Chrome UX Report, top markets of either technology.
Real user performance
| Metric | Optimizely | SiteSpect |
|---|---|---|
| LCP | 2 s | 1.3 s |
| INP | 100 ms | 125 ms |
| CLS | 0.05 | 0.05 |
| TTFB | 800 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.