What the encryption actually is
Your master password is stretched into a key with PBKDF2-SHA256 over 600,000 rounds — the current OWASP floor — and the vault is encrypted with AES-256-GCM. A fresh random salt and a fresh random initialisation vector are used every time it is written, so the same entry never produces the same ciphertext twice.
Only the ciphertext is stored. The master password is never written anywhere, and the derived key is discarded when you lock the vault or close the tab. GCM also authenticates the data, so a modified vault fails to open rather than decrypting to nonsense.
Be clear about the threat model
This protects your entries from anyone who reads your browser's storage or gets hold of your backup file without knowing the master password. That is a real and useful guarantee.
It does not protect you from malware on the machine, a malicious browser extension, or someone watching you type. Nothing that runs inside a browser can. If your threat model includes those, use a dedicated password manager with a hardened client.
There is no recovery, and that is the design
Nobody can reset the master password, because nobody has it — there is no server, no account and no email on file. Forgetting it means the vault is unreadable, permanently.
Export a backup and keep it somewhere safe. The backup is the encrypted envelope, so it is safe to store in a cloud drive or email it to yourself — it is useless without the master password.
The generator
Passwords are generated from crypto.getRandomValues, not Math.random, and use rejection sampling so no character is more likely than another. At least one character from each selected set is guaranteed, then the whole thing is shuffled so the guaranteed characters are not always at the front.
Twenty characters of mixed case, digits and symbols is around 130 bits — far beyond anything that can be brute-forced.
Frequently asked questions
Is a browser-based vault safe enough?
For low-to-medium stakes — forum logins, throwaway accounts, shared household passwords — yes, and it is much better than a text file or reusing one password. For your bank and your email, a dedicated password manager with a hardened client and a security audit is the right tool.
Why does unlocking take a second?
Deliberately. The 600,000 PBKDF2 rounds cost you about a second once, and cost an attacker trying millions of guesses about a second each. That asymmetry is the entire point.
Can I sync it between devices?
Only by exporting the encrypted backup and restoring it on the other device, using the same master password. There is no server, so there is nothing to sync through.
Where is my data kept?
In this browser's local storage, on this device. It is never sent anywhere, which also means it does not follow you to another browser unless you export a file and import it there.
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