Audience
Privacy-conscious users
About Aster Mail
Aster Mail is a free, open-source, end-to-end encrypted email service for people who want real privacy without the technical overhead. All encryption happens on your device before anything reaches our servers, so we have zero access to your messages or metadata.
Aster uses standard OpenPGP with portable RSA-4096 keys, so you're never locked in. Your keys work with GPG, Thunderbird, or any PGP client, and they're discoverable through WKD and public keyservers. Aster-to-Aster messages use a Signal-inspired X3DH and Double Ratchet protocol for forward secrecy.
Every plan includes encrypted email, custom domain support, free aliases, tracker protection, and full access across web and desktop. The entire codebase is published under AGPL v3 on GitHub, fully auditable, with a public warrant canary and documented vulnerability disclosure.
Free plan includes 10 GB encrypted storage, 5 aliases, and 1 custom domain. Paid plans start at $2.99/month. Servers located in Germany.
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Pricing
Free Version:
Free Version available.
Integrations
No integrations listed.
Company Information
Aster Mail
Founded: 2025
United States
astermail.org
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Product Details
Platforms Supported
Cloud
Windows
Mac
Linux
iPhone
iPad
Android
Chromebook
Training
Documentation
Videos
Support
Online