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Preview of Hermes

Hermes by Omar Criacci

End-to-end encrypted messaging using ECDH key exchange and AES-GCM encryption. Secure your online conversations.

5 (7 reviews)5 (7 reviews)
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End-to-end encrypted messaging using ECDH key exchange and AES-GCM encryption. Secure your online conversations.Your private keys never leave your device. Access your local vault securely with your Master Password.Easily manage trusted contacts. Share your ECDH public key and verify others to establish secure channelsBring End-to-End Encryption to WhatsApp, Telegram, Messenger, and any other web-based chat.
About this extension
Hermes adds end-to-end encryption to any messaging platforms, including those that already have it, like WhatsApp, Telegram, and Facebook Messenger, using ECDH P-256 key exchange and AES-GCM encryption.

You create a master password that protects your encryption keys. To communicate securely with someone, you exchange public keys. Then you encrypt messages before sending and decrypt messages you receive.

Both you and your contact need the extension installed to communicate securely. Works with any text-based messaging platform.
All encryption happens locally on your device. Your keys never leave your browser.

Hermes features:
- ECDH P-256 key exchange
- AES-GCM 256-bit encryption
- Local storage with PBKDF2-protected vault (100k iterations)
- Profile management for contacts
- Clipboard integration
- No data collection or external servers
- Open source, vanilla JavaScript. No external libraries/dependencies
Rated 5 by 7 reviewers
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Permissions and data

Required permissions:

  • Get data from the clipboard
  • Input data to the clipboard

Data collection:

  • The developer says this extension doesn't require data collection.
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Version
2.0.2
Size
49.26 KB
Last updated
17 days ago (Jan 20, 2026)
Related Categories
  • Privacy & Security
  • Social & Communication
License
GNU General Public License v3.0 only
Version History
  • See all versions
Tags
  • privacy
  • security
  • social media
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