How to play
Tap a cell, then tap a number. Clear removes a number you typed.
A red digit is repeated in its row, column, or box.
Play again loads another puzzle.
Rules
- Each row, each column, and each 3×3 box must contain the digits 1 through 9 once.
- Printed numbers cannot be changed.
- The puzzle is solved when every cell is filled and none of those groups repeats a digit.
Common questions
Are the puzzles the same every visit?
There are a few beginner boards. Play again picks one at random.
Is there a hint button?
No. The red marks are the only help, and they appear when a digit is repeated.
Is my grid uploaded?
No. The puzzle is solved on this page.