There are two ways in, and both create the same free account. There is no password to set.
On the website
Go to app.justonce.ai/login and pick whichever sign-in you prefer:
Continue with Google or Continue with Microsoft — signs you in with that account in one step.
Continue with Email — enter your address and we email you a one-time sign-in code. The email comes from JustOnce <[email protected]> with the subject "123456 is your JustOnce sign-in code". Type the code within 10 minutes.
The first sign-in creates your account and your personal space. Your Free plan starts immediately, including the welcome bonus (see Welcome bonus: your first 90 days) — no card required.
From your AI app
You don't need to visit the website first. Add JustOnce as a connector in Claude, ChatGPT or another MCP client (see How connecting works). When the app opens the JustOnce sign-in window, choose Google, Microsoft or your email address. If you're new, your account is created right there.
Next comes a JustOnce screen that says Your free JustOnce account is ready and asks you to connect the app. It lists what the app will be able to do (search and read your memories; save, update and delete them; read your profile and context; see your categories) and shows the email you're signed in as. Choose Allow to finish connecting, or Cancel. You'll see the same screen, without the first line, each time you connect another app.
If the window says it needs a confirmed email address, try again with an email code or Google.
Afterwards, sign in at app.justonce.ai with the same method to see and manage everything you've saved.
Tips
Use the same method each time. If you sign in with Google one day and an email code the next, JustOnce will tell you which method your account already uses — see "I already have an account with this email".
If the code doesn't arrive within a minute, check Junk or Spam for "is your JustOnce sign-in code". More in My sign-in code didn't arrive.
You stay signed in on that browser; after about a day of inactivity you'll be asked to sign in again (see Sessions: why you were signed out).