Keygrain

One secret. Every password. Nothing to breach.

Keygrain derives unique passwords from a single secret you remember. No vault. No database. No account. Just math.

Free and open source · Works offline · All platforms

How it works

Remember one secret. Get a unique password for every site.

Your one secret
↓ just add a site
github.comkX9m#P2vL$nQ7w
gmail.comhT4&Bm8pJ!kY2rW
netflix.comQn6$wR3mXt@Lp9v

Same secret + any site = unique password. Computed locally, never stored.

Security

Designed to minimize attack surface.

Argon2id Key Stretching

64 MiB memory, 3 iterations. Makes brute-force attacks against your secret computationally expensive (~1s per guess).

No Password Database

No password database exists. Passwords are recomputed on demand. There is nothing to breach.

E2E Encrypted Sync

Site configurations (not passwords) sync between devices using AES-GCM encryption derived from your secret. The server sees only ciphertext.

Get Keygrain

Free and open source. No account required.

Chrome

Coming soon

Chrome, Edge, Brave, Arc

Firefox

Coming soon

Firefox 109+

Android

Download APK

Android 8+ · No Play Store needed

Python CLI

pip install keygrain

Python 3.10+ · CLI + library