About the game
Classic 9x9 sudoku. Click a cell and enter a number from 1 to 9, and each appears once per row, column and box. To delete a number, enter it again on the in game keypad.
Sudoku is the best known number logic puzzle, and it needs no arithmetic at all. The 9x9 grid is split into nine 3x3 boxes, and some numbers are already filled in. The rest is solved by pure logic, so a good sudoku always has a single solution.
Sudoku Classic belongs to the Sudoku variant in the Brain teasers world and joined the catalogue on March 18, 2025. The rules, levels and on-screen language are set by the game’s creator, and a short guide appears on its start screen.
How to play
- Click an empty cell and enter a number from 1 to 9.
- Each number may appear only once in every row, column and 3x3 box.
- To delete a number, enter it again on the in game keypad.
- The sudoku is solved when the whole grid is filled with no repeats.
Full rules: Sudoku rules: how to play and how to solve it
Three tips for faster solving
- Start with numbers that already appear often, it is easier to see where they are still missing.
- For each cell, think which numbers cannot go there, what remains is your answer.
- When a cell has a single possibility, fill it at once, it opens up its neighbours.
