Messages only the recipient can open

Secret Keeper encrypts on your device and produces a self-contained envelope.

Send it through any messenger, email or forum - only the people it is addressed to can read it.

Why Secret Keeper

No servers, no accounts

Your address is your public key - sk1…, about 60 characters. No registration, no phone number, nothing stored in a cloud. The whole identity is restored from 12 BIP-39 words.

A self-contained envelope

X25519 key agreement plus XChaCha20-Poly1305. Every envelope carries a key slot for each recipient - and for you, so your own history stays readable. Deliver it over any channel.

Files of any size

Files are encrypted into the .skf container in streaming chunks: a movie encrypts as easily as a note, and truncation or chunk reordering is detected.

Everything stays local

Contacts and history live only on your device. Backup is a single encrypted .skb archive that only your key opens.

If the phone ends up in the wrong hands

The vault is locked with a PIN or biometrics. The rest is designed for pressure, not just for loss.

Wipe on brute force

A configurable number of wrong PIN attempts erases the vault.

Duress PIN

A second PIN that opens an empty profile - or silently wipes the real one.

Clipboard hygiene

Copied secrets are cleared from the clipboard after a timeout.

Try it on your platform

iOS, Android, macOS, Windows - and the browser extension.

Download Secret Keeper