Sudoku is a classic logic-based number placement puzzle. Fill a 9×9 grid so that every row, column, and 3×3 box contains each digit from 1 to 9 exactly once. No maths needed — just pure logic.
Every row must have the numbers 1–9 with no repetition. Every column must have the numbers 1–9 with no repetition. Each of the nine 3×3 boxes must have the numbers 1–9 with no repetition.
Use Notes mode to pencil in candidates. Scan rows, columns, and boxes for cells where only one number fits. Look for naked singles and pairs to eliminate candidates quickly.
Easy has 38+ clues. Medium has about 30 clues. Hard has about 23 clues. All puzzles are computer-generated with a unique solution.
Is this Sudoku game free?
Yes — completely free, no sign-up, no download, no ads. Play instantly in any browser.
Can I play on my phone?
Yes. The game is fully responsive and works on phones, tablets, and desktops.
How does Notes mode work?
Enable Notes, select a cell, then press a number to toggle a small candidate note. Entering a final number clears the notes automatically.