Cart Functionality vs Fastspring
Head-to-head usage across the sites we track.
Top sites by authority
Cart Functionality · Fastspring · how many of each technology's sites sit in the web's highest authority tiers
Open Page Rank 9+
141
0
Open Page Rank 8+
2,489
2
Open Page Rank 7+
10,234
4
Open Page Rank 6+
20,359
4
Open Page Rank 5+
37,013
6
Open Page Rank scores 0 to 10 from the open web link graph; 9+ covers only a few hundred domains worldwide.
By country
Cart Functionality · Fastspring · share of sites in each country using one or the other
United States
729,127
44
United Kingdom
237,218
20
India
207,181
23
Germany
193,696
16
France
180,639
13
Canada
165,082
18
Brazil
144,613
16
Spain
143,412
13
Audience countries from the Chrome UX Report, top markets of either technology.
Real user performance
| Metric | Cart Functionality | Fastspring |
|---|---|---|
| LCP | 1.7 s | 1.9 s |
| INP | 75 ms | 50 ms |
| CLS | 0 | 0 |
| TTFB | 700 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.