Open Source · Zero Server · Post-Quantum Ready
Private chats on
any platform
ciphertext overlays a lock button on the message box of any supported site. Encrypt locally — the platform only ever sees ciphertext, and your keys never leave your device.
Discord
Slack
WhatsApp Web
Telegram Web
Instagram DMs
X / Twitter
Facebook Messenger
Firefox: any site (optional)
Lock on every message box
ciphertext detects the input and overlays a lock button directly on it. Click, type, send.
Post-quantum ready
Hybrid ECDH P-256 + ML-KEM-768. An attacker must break both to read a message.
AES-256-GCM
Every message encrypted with a unique random key. Platforms only see ciphertext.
Keys stay local
Your private key never leaves your browser. Stored in chrome.storage.local, never synced.
Group encryption
One message, multiple recipients. Each gets their own encrypted key slot.
GPG compatible
Import OpenPGP public keys from Kleopatra or any GPG keychain.
Captured automatically by the Selenium end-to-end run against LibreWolf (
npm run test:screenshots).Support the project
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ciphertext is free, open source, and has no ads or subscriptions.
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