Proton Mail vs Zimbra
Head-to-head usage across the sites we track.
Top sites by authority
Proton Mail · Zimbra · how many of each technology's sites sit in the web's highest authority tiers
Open Page Rank 9+
8
0
Open Page Rank 8+
51
38
Open Page Rank 7+
205
156
Open Page Rank 6+
433
274
Open Page Rank 5+
754
420
Open Page Rank scores 0 to 10 from the open web link graph; 9+ covers only a few hundred domains worldwide.
By country
Proton Mail · Zimbra · share of sites in each country using one or the other
United States
5,830
840
India
1,985
718
United Kingdom
2,125
356
France
1,914
514
Germany
1,938
440
Brazil
1,300
817
Canada
1,752
270
Netherlands
1,445
321
Audience countries from the Chrome UX Report, top markets of either technology.
Real user performance
| Metric | Proton Mail | Zimbra |
|---|---|---|
| LCP | 1.7 s | 1.7 s |
| INP | 75 ms | 100 ms |
| CLS | 0 | 0 |
| TTFB | 700 ms | 600 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.