Proton Mail
Proton Mail is the world’s largest secure email service with over 100 million users. Available on Web, iOS, Android, and desktop. Protected by Swiss privacy law.
Proton Mail is commercial email server software made by Proton AG. It was first released in 2014. Its English Wikipedia article has about 12k readers a month on phones.
- Made by
- Proton AG
- Since
- 2014
- Wikipedia readers on phones
- 12k a month
- Source code
- Closed
Judgement
- What it is
- Complete system
- What it does
- End-to-end encrypted email from Switzerland, bundled with Proton's calendar, drive, VPN and password manager.
- Adopt it when
- Privacy is your first concern and you want encrypted email, especially between Proton users.
- Watch out
- Desktop email clients need the paid Bridge app, and encryption limits server-side search and integrations.
- Ready for
- Production-ready
- Runs as
- Cloud service, desktop app and mobile app
- What the license allows
- Closed source: you use it under the maker's terms and cannot change or resell the code.
Judged on 2026-11-03 from the maker's description and Wikipedia. The license and age lines are worked out directly.
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Commercial
Under it
Every program, Proton Mail included, runs on a microchip.
The description is the maker's own, quoted as written. Facts come from Wikipedia and refresh weekly. Readers are counted on Wikipedia's mobile site only, because automated traffic that Wikimedia does not flag inflates desktop counts.