Welcome

This is a private mailbox for two devices. It exists only until you delete it, and only someone you hand your pairing code to can send to it.

Everything below happens in this browser tab. Nothing is uploaded until you create the mailbox, and even then it is ciphertext.

There is no recovery

Keeping the twelve words and your browser data on the same device is enough. Keeping them apart is better.

Your secret phrase

These twelve words rebuild your keys on any device. Write them down or put them in a password manager. Anyone who has these words can read your messages.

Confirm your phrase

Type the twelve words back, separated by spaces. This is the only time we will show them.

Create your identity

Your keys are generated here, on this device, and wrapped under a key derived from your phrase. The private half never leaves the browser and is not extractable once loaded.

Create your mailbox

Your mailbox starts empty and expires after 14 days. It has a random address and two separate capabilities: one you hand out so people can write to you, and one you keep so you can read.

Pair a contact

Give this code to the other person. It contains your mailbox address and a write-only capability — it does not let them read your mail. One contact per mailbox.

Verify

Paste their code below. Then compare the fingerprints out loud — in person, or over a call you already trust. If they match, nobody is impersonating your mailbox.

You're set up

Your mailbox is ready: paired, private, and set to expire on its own.

• Every message is padded to 16,384 bytes before it leaves this device.
• Mail is written with a capability, so the relay cannot tell who wrote to you.
• To test alone, paste your own code in the app and message yourself.