Number puzzle
Sudoku
Fill every row, column, and 3 x 3 box with the numbers 1 through 9.
Sudoku
Choose a difficulty, fill the empty cells, and complete the board without breaking Sudoku rules.
How to Play
- Select an empty cell on the board.
- Enter a number from 1 to 9 with the keyboard or the number pad.
- Use Backspace, Delete, 0, or Clear to erase an editable cell.
- Complete the entire board correctly to solve the puzzle.
Rules
Each row must contain the numbers 1 through 9 without duplicates. Each column follows the same rule.
Each 3 x 3 box must also contain the numbers 1 through 9 without duplicates. Fixed clue cells are part of the puzzle and cannot be changed.
Strategy Tips
- Start with rows, columns, or boxes that already contain many clues.
- Look for numbers that can fit in only one remaining cell.
- Compare overlapping rows, columns, and boxes before placing a number.
- Avoid guessing until logical options are exhausted.
Saving and Best Times
Sudoku saves the best completion time separately for Easy, Medium, and Hard using localStorage. A time is saved only after the puzzle is solved correctly.
Restart restores the current puzzle to its original clues and resets the timer. New Puzzle loads a different puzzle for the selected difficulty when one is available.
Controls
Use mouse click or tap to select a cell. Number keys enter values, Backspace, Delete, or 0 clears a cell, and arrow keys move the selection around the board.
The on-screen number pad works with mouse and touch controls on desktop and mobile.
Related Games
For more puzzle games, try 2048, Minesweeper, or Number Guess.