What "zero-knowledge" means
Most websites keep a copy of your password (hashed) and can see everything you store. A zero-knowledge vault works differently: the secret that unlocks your data is created on your device from your master password, and it never leaves it. We hold your vault, but not the key.
We never receive your master password, we can't decrypt your vault, and we can't hand readable copies of it to anyone.
What happens when you log in
- Your browser stretches your master password. It runs PBKDF2-SHA256 600,000 times with a random salt that's unique to your account. This makes guessing attacks slow and expensive.
- Two separate keys are derived from it using HKDF: an encryption key that stays in your browser, and an authentication key that proves to us it's you.
- Only the authentication key is sent. We hash it again with Argon2id before storing it, so even a stolen copy of our database can't be used to log in or to unlock your vault.
- Your browser unlocks your vault key with the encryption key, then decrypts your items in memory. Locking the vault (or closing the tab) wipes them.
How your items are protected
| Layer | What it does |
|---|---|
| Vault key | A random 256-bit key, unique to you, encrypted with the key derived from your master password. |
| Item keys | Every password or note gets its own random key. Item content — name, username, password, website, notes, even the folder — is encrypted with AES-256-GCM, which also detects tampering. |
| Sharing keys | Each account has an RSA-OAEP 2048-bit key pair. Sharing an item encrypts just that item's key for the other person's public key. |
| Family & team keys | Each family or team has its own key, handed to members encrypted with their public keys. |
| Recovery key | A second copy of your vault key, encrypted with a random recovery key that only you are shown. |
Protection beyond encryption
- Two-factor authentication and passkeys stop someone who learns your password from logging in.
- Account lockout: after 5 wrong passwords or 2FA codes, logins are paused for an hour and you're emailed. (Your passkeys still work, and the lock can't be used to discover whether an account exists.)
- Rate limiting on codes, password resets and other sensitive actions slows down guessing.
- Strict browser security headers (Content-Security-Policy, HSTS, no framing) make common web attacks much harder.
- Auto-lock wipes decrypted data from memory after a period of inactivity you choose.
- Clipboard clearing: copied passwords are removed from your clipboard after 30 seconds.
- Activity log: see every login, failed attempt and important change on your account.
- Security emails whenever your account's security settings change: master password, email address, 2FA, passkeys or recovery key, plus a lockout warning after repeated failed logins. Changes to items in your vault don't send emails.
The trade-off: you hold the key
Because we can't decrypt your vault, we also can't reset your master password for you. That's why you're given a recovery key when you sign up. With it, you can set a new master password and keep everything. Without it, you can still regain your account, but the items in your vault are permanently erased — there's no back door, for anyone.
Print your recovery key or store it somewhere offline and safe — not inside your vault.
Questions
Can PasswordPal staff see my passwords?
No. Your items are encrypted before they leave your device and we never have the key. Administrators can see account details such as your email address and plan, but not vault contents.
What if your servers are hacked?
An attacker would get encrypted data and Argon2id hashes of authentication keys. To read anything they would need to guess your master password, and each guess costs 600,000 rounds of hashing. A long, unique master password keeps you safe.
Why does logging in take a second?
That pause is your browser stretching your master password 600,000 times. It's deliberate — it makes guessing attacks enormously slower.
What happens if I forget my master password?
Use "Forgot password" and your recovery key to set a new one without losing anything. If you've lost the recovery key too, you can reset your account, but the vault contents are erased.