jeden.day – habit tracker
A habit tracker with no password
A password is one more thing to remember for an app you open for ten seconds a day. jeden.day has none. Signing in is an emailed link or an eight-digit code, and once you are in you can add a passkey so the next time is your fingerprint, face or device PIN.
Sign in with your email
Enter your address and you receive one mail with a link and a code. Open the link on the device you are on, or type the code into the device you started from — so an inbox open on a laptop can sign in a phone. Either proof works once, for fifteen minutes. There is no separate signup: the first sign-in creates the account, and the same flow is how you get back in if you ever lose every device.
Nothing about the flow reveals whether an address already has an account, and a wrong code five times only burns that one attempt, never your inbox.
Then add a passkey
A passkey is a credential your device holds — in iCloud Keychain, Google Password Manager, Windows Hello or a password manager — and unlocks with the fingerprint, face or PIN you already use. Add one from the account menu after signing in and the next sign-in is a single tap on the sign-in screen. Passkeys cannot be phished, because the browser only ever offers them to the site that registered them.
Email sign-in keeps working alongside, so a passkey you lose with a device is an inconvenience, not a lockout.
Sessions you can see
A sign-in lasts ninety days on that device. From the account menu you can sign out every other session, and deleting the account ends all of them. Sensitive changes — a new passkey, a new email address, connecting an AI agent — ask you to prove it is you again if your sign-in is older than fifteen minutes, with the passkey on that device or a fresh mail.
Or do not sign in at all
The whole tracker works without an account, in your browser. Signing in is for syncing to a second device and for the downloadable copy of your data; the no-account page explains what stays where.
Questions
What if I do not receive the mail?
Check the spam folder first. A second request within a few minutes re-sends nothing on purpose — the link and code already in your inbox still work — so wait for the first mail rather than requesting again immediately.
Do I need a passkey?
No. It is a convenience. Email sign-in alone is a complete way to use the account.
Can I sign in with Google or Apple?
No. There is no third-party sign-in, which also means no third party learns when you use the app. Your email provider is the only other party involved.
Can I change my email address?
Yes, from the account menu. The new address confirms it by mail; your habits, passkeys and sessions are untouched, and the old address is told where the account went.
Try it now
The grid works in your browser without an account. Sign in later if you want it on a second device.
Open jeden.day