Microsoft 365 vs Outlook Web App
Head-to-head usage across the sites we track.
Top sites by authority
Microsoft 365 · Outlook Web App · how many of each technology's sites sit in the web's highest authority tiers
Open Page Rank 9+
64
0
Open Page Rank 8+
1,815
13
Open Page Rank 7+
10,501
32
Open Page Rank 6+
24,517
49
Open Page Rank 5+
49,547
67
Open Page Rank scores 0 to 10 from the open web link graph; 9+ covers only a few hundred domains worldwide.
By country
Microsoft 365 · Outlook Web App · share of sites in each country using one or the other
United States
463,081
2,704
United Kingdom
167,042
1,345
Germany
135,802
1,268
Canada
108,907
1,153
India
102,571
1,547
Netherlands
97,414
923
Australia
93,854
665
France
89,127
1,078
Audience countries from the Chrome UX Report, top markets of either technology.
Real user performance
| Metric | Microsoft 365 | Outlook Web App |
|---|---|---|
| LCP | 1.8 s | 1.7 s |
| INP | 75 ms | 75 ms |
| CLS | 0 | 0 |
| TTFB | 800 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.