Sudoku
Complete the classic sudoku puzzle by filling in missing numbers
Game time:
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How to Play Sudoku
In sudoku, the objective is to fill a 9 × 9 grid with digits so that each column, each row, and each of the nine 3 × 3 subgrids that compose the grid contains all of the digits from 1 to 9, with no repeats anywhere.
Select a cell then click a number from the number pad above the sudoku board, or type a number directly if you are playing on a device with a keyboard, e.g. a laptop. Fixed (pre-filled) cells cannot be changed. Use Check at any time to highlight incorrect entries in red, or Solve to reveal the complete solution.
Sudoku Tips & Strategy
- Scan rows, columns and boxes for numbers that already appear twice out of three times in a 3x3 box — the missing cell for that number is often forced.
- Work the easy numbers first. Numbers that already appear 5-6 times on the board are usually the fastest to place in their remaining spots.
- Look for cells with only one possible number before guessing — check what digits are already used in that cell's row, column and box.
- Start with a lower difficulty if you're new to sudoku; Easy and Medium leave more starting digits, which narrows down the possibilities faster.
Frequently Asked Questions
Fill the 9x9 grid so that every row, every column, and each of the nine 3x3 boxes contains the digits 1 to 9 exactly once, with no repeats.
Each difficulty removes a different number of starting digits from a fully solved grid: Easy removes 35 cells, Medium 45, Hard 55, Expert 60, and Extreme 65. Fewer starting digits means more deduction is required to solve the puzzle.
Yes. Select a cell, then type a number from 1-9 on your keyboard to fill it in, or use the on-screen number pad if you are on a touch device.
Check compares your current entries against the solution and highlights any incorrect numbers in red, without revealing the correct answer.
Solve immediately fills in the complete, correct solution. Use it if you want to see the answer rather than keep working on the puzzle.