Encrypt a message
FAQ
Does your server ever see my data?
No. Everything is encrypted in your browser with AES-GCM-256 before upload. The key is derived from a random value we put in the URL fragment (#…), which browsers never send to servers.
What changed vs the old AWS version?
Crypto upgraded from AES-CBC + PBKDF2 10k iterations to AES-GCM-256 (authenticated) + PBKDF2-SHA256 600k iterations. 16-byte salt, 12-byte random IV per message. The blob format is tagged "RSv1" so we can evolve it later.
How big can a file be?
Up to 2 GB on desktop browsers. WebCrypto needs the whole file in memory, so very large files depend on how much RAM the browser will give us.
Can I trust you?
The whole site and Worker are open source on GitHub — read every line yourself, or fork it and run your own. Inspect the network tab while you use the site: you'll only ever see ciphertext leaving your machine.