Compare Aster Mail vs. Proton Mail

Aster Mail is a complimentary, open-source email service that offers end-to-end encryption for users seeking genuine privacy without cumbersome technical requirements. The encryption process occurs directly on your device, ensuring that our servers never have access to your messages or any associated metadata. Utilizing the widely accepted OpenPGP standard with RSA-4096 keys, Aster ensures that you are not bound to a single provider; your keys can be used seamlessly with GPG, Thunderbird, or any compatible PGP client, and they are easily discoverable via WKD and public key servers. For communications between Aster users, the service employs a Signal-inspired X3DH and Double Ratchet protocol, providing enhanced forward secrecy. Each subscription tier comes with encrypted email capabilities, support for custom domains, free aliases, protection against trackers, and unrestricted access across both web and desktop platforms. The complete codebase is available under the AGPL v3 license on GitHub, allowing for thorough audits, and it features a public warrant canary along with a clear vulnerability disclosure policy. The free tier provides 10 GB of encrypted storage, along with 5 aliases and 1 custom domain. Paid subscriptions begin at just $2.99 per month, and all servers are conveniently located in Germany, ensuring compliance with stringent data protection regulations. Users can feel secure knowing their communications are protected by top-notch encryption standards.

Secure your company’s communications with Proton Mail — the business email solution trusted by over 50,000 organizations. With end-to-end encryption built in, your internal and external communications stay confidential by default. Proton Mail helps your business meet GDPR, HIPAA, and other compliance standards, while giving you full control over your data under strong Swiss privacy laws. Empower your team with encrypted email and calendar, support for your custom email domains, professional branding, and simple migration from providers like Google Workspace or Microsoft 365 — no IT team required.