Proven Sudoku
Sudoku with no account
Open the page and play. There is nothing to sign up for, and no email to hand over.
There is no login here because there is nothing to log in to. No account is made for you in the background either.
How it works without one
The board is not sent to you. It is worked out on your own device from today's date. Everyone's device works out the same one, which is how the whole world gets the same three boards each day with nobody signed in.
Your progress is saved in your own browser as you play. Close the tab and come back, and the grid is where you left it.
What stays on your device
- Your part finished grid.
- Your pencil marks.
- Your time on the clock.
- Your own record of past solves.
None of that is sent to us. We could not show it to you on another device even if you asked, because we do not have it.
What does leave your device
A small count when a board is put on your screen, and when you start, finish or give up on one. It carries the day, the level, how long you took and how far you got. Nothing else. It has no name, no email and no account attached, because there is none to attach.
If you choose to share a result, the link holds the day, the level and your time. It never holds the board or its answer.
Privacy lists all of it, including what our host logs the way every web host does.
What you give up
This is the real trade, and it is worth knowing before you build a streak.
| Thing | With an account elsewhere | Here |
|---|---|---|
| Playing on your phone and laptop | Same progress on both | Separate on each. They do not meet. |
| Clearing your browser data | Progress comes back when you sign in | It is gone, and we cannot restore it |
| Your run of solves | Kept on their server | Kept on your device only |
| Handing over an email | Usually required | Never asked for |
So the trade is plain. Nothing to sign up for and nothing held about you, in exchange for a record that lives on one device and can be wiped. Stats and streaks shows what that record holds.
Common questions
Will I lose my streak if I clear my browser?
Yes. It lives in your browser, so clearing site data takes it with it. There is no copy anywhere else.
Can I move my progress to a new phone?
Not today. There is nothing to sign in to, so there is nothing to carry it across.
Do I need an account to share a result?
No. Sharing makes a link from the day, the level and your time. How to share your result shows what is in it.
Is any of this different in the app?
The apps are not released yet. Everything on this page describes the web version, which is the only one you can play today.