IIS vs Uvicorn
Head-to-head usage across the sites we track.
Top sites by authority
IIS · Uvicorn · how many of each technology's sites sit in the web's highest authority tiers
Open Page Rank 9+
53
1
Open Page Rank 8+
1,275
22
Open Page Rank 7+
5,011
58
Open Page Rank 6+
9,561
81
Open Page Rank 5+
15,981
105
Open Page Rank scores 0 to 10 from the open web link graph; 9+ covers only a few hundred domains worldwide.
By country
IIS · Uvicorn · share of sites in each country using one or the other
United States
121,069
451
India
60,068
314
United Kingdom
43,214
209
Italy
39,691
173
Brazil
35,276
210
Germany
31,791
282
Canada
31,780
179
Türkiye
31,323
141
Audience countries from the Chrome UX Report, top markets of either technology.
Real user performance
| Metric | IIS | Uvicorn |
|---|---|---|
| LCP | 1.6 s | 1.9 s |
| INP | 75 ms | 100 ms |
| CLS | 0 | 0 |
| TTFB | 700 ms | 700 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.
Sites that switched
Domains that dropped one technology and adopted the other within about a year, data nobody else gives away free.
Uvicorn to IIS
| Domain | When |
|---|---|
| linestreetvet.com | May 2026 |
| bemidjivethospital.com | Feb 2026 |