How it works
- 1Take a photo of the sudoku, upload a screenshot, or type the numbers in.
- 2Check the numbers it read. Anything it wasn't sure about is marked.
- 3Press play to go through the solution one step at a time, or drag along the line to any step.
- 4Every step comes with its reason: the technique, the cells involved, and why only one number fits.
A solver that teaches
Most solvers fill in the whole grid at once. That gets you an answer, but it doesn't help with the next puzzle. This one solves the way a person does: it always takes the easiest move on the board, singles first, then techniques like pointing pairs and X-Wing, so every step is one you could have found yourself.
Every step is proven from the numbers on the board. When a cell can only hold one number, it names the numbers that rule out the rest. When no simple move is left, it shows what goes wrong if you try the other option.
Questions
Is my photo uploaded anywhere?
No. The picture is read in your browser, on your device. Only the puzzle's numbers ever leave it, and only if you copy a link or open a co-op room.
What if it reads a number wrong?
Tap the cell and type the right number. Numbers it wasn't sure about are marked in yellow, and the solver tells you when the puzzle has no solution or more than one, which usually means a misread.
Can it solve any sudoku?
It finds the answer to any classic 9×9 sudoku that has exactly one solution. Puzzles with no solution or several are pointed out instead.
Will it show me the whole solution?
Only if you want it to. You go one step at a time and can stop whenever you like, then finish the puzzle yourself right here on the board.
Can I solve it with a friend?
"Solve it with a friend" opens a co-op room with your puzzle. Anyone with your invite link can join, as a guest if they like, and you fill in the board together.