Updated 2026-09-25
The first time you open Atrium, you create a master password. Every key that protects your vault, notes and calendar is unlocked by it.
What makes it different
- It never leaves your device. Your browser runs it through Argon2id, a deliberately slow function, to produce your key. Our server receives only a value derived from it that confirms you typed it correctly, and that value can't decrypt anything.
- One password covers all three rooms. Vault, notes and calendar share the same key, so you only have one thing to remember.
- We can't reset it. There is no "forgot password" email for your master password, because we never have it.
Choosing a good one
Use a long passphrase you don't use anywhere else, such as four or five unrelated words. The setup screen shows how strong it is. A weak master password is the one weakness no amount of server security can fix.
Save your Recovery Kit
Right after you create your master password, Atrium gives you a Recovery Kit. Saving it is required, and it is your only way back if you forget the password. Read Your Recovery Kit before you put it away.
Changing it later
You can change your master password in Settings while unlocked. Your data doesn't need to be re-encrypted: only the wrapping around your account key changes.