Why do I have to enter my password when I open chat?

Your password protects your key backup

For end-to-end encryption you need a private key that only lives on your device. But what if you lose your phone or buy a new one? You'd lose all your old chats.

That's why we keep an encrypted backup of your private key on our server. The backup is locked with your account password: only you — with your password — can unlock it. We only ever see it encrypted.

When do we ask for your password?

• First time opening chat on a device: to unlock the backup or (on first ever use) to securely store a new key
• New phone or reinstalled the app: so we can decrypt your old chats
• After changing your password: we then re-encrypt your backup with the new password

Good to know:

• Your password is used only locally to unlock the key — it's never sent to our server in plain text
• We never store the password on your device
• We can never see your password — that's technically impossible
• Argon2id makes brute-force attacks extremely slow, even if someone stole the encrypted backup