Zero-knowledge server
We encrypt in your browser. Our servers store only ciphertext — we literally cannot read your message, even if compelled by law.
You're heading into the unknown — climbing a mountain, traveling solo, facing surgery. If you don't check in within 7 days, your encrypted message reaches the people you choose. They need 3 of 5 keys to read it. The server never sees a word.
Create your encrypted message100% zero-knowledge · Shamir's Secret Sharing · Self-destructing after read
Your message is protected by Shamir's Secret Sharing — the same mathematics used by intelligence agencies. Here's how it works.
Write your message or upload files. Everything is encrypted in your browser before it ever leaves your device.
Your encrypted message is split into 5 unique key fragments. No single fragment reveals anything.
Each of your 5 trusted people receives one fragment — a personal key only they possess.
If you don't check in within 7 days, the dead man's switch activates. Your recipients are notified.
Any 3 of your 5 key holders submit their fragments. The threshold is met — your message decrypts.
The message is displayed once. The moment it's read, every trace is permanently deleted from our servers.
Even if 2 people lose their key or refuse — the message still gets through.
We encrypt in your browser. Our servers store only ciphertext — we literally cannot read your message, even if compelled by law.
No single person holds the full key. No single server holds the full message. Compromise one part — the secret stays safe.
After the threshold is met and the message is read, every fragment and every encrypted byte is permanently purged. No backups.
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