.proton Domain

The .proton domain extension is used for Proton's privacy-focused products, including encrypted email, VPN, cloud storage, password management, and video conferencing. People rely on these tools for private communication, so a brand extension helps them tell real Proton addresses from imitations. Proton Technologies Ltd applied for the extension.

Addresses ending in this extension bring Proton's product infrastructure into one namespace that Proton runs itself. That means its services no longer depend on registries it does not govern, and no one outside Proton can register a name that falls under it. Users get a simple rule to follow: if an address ends in .proton, Proton issued it. This helps people spot phishing attempts that copy Proton's domains on open extensions. For Proton, a dedicated extension protects the addresses its users depend on for encrypted communication.