The goal
Fill each row, column and 3 × 3 box with the numbers 1 through 9, without duplicates. Original clues cannot be changed.
Logic · 5–15 MIN
How to play ↓Sudoku.
Nine numbers. One satisfying challenge.
Getting your game ready…
How to play: Sudoku
The controls
Select a cell and use the number pad or your keyboard. Turn on Notes for pencil marks. Erase removes an entry; Undo takes back your last action. Check marks errors without solving the puzzle.
A little strategy
Start with an almost complete row or box. Look for the only place a number can go. Every generated puzzle has exactly one solution.
Does every puzzle have a solution?
Yes. Each generated board is checked for exactly one solution. Difficulty changes the number of clues, rather than representing a formal technique rating.
Where is my progress saved?
Progress stays in this browser. An optional account lets you save an encrypted backup and restore it on another device from My account. There is no automatic sync.
A GUIDE TO KEEP GOING
Read the guide ↗Sudoku for beginners: find what is missing
Sudoku is not an arithmetic exercise. It is a placement problem: where a number can go, and where it cannot.