How to use the sudoku solver
- Type the puzzle’s numbers into the grid (arrow keys move between cells), or paste all 81 digits.
- Press Use as puzzle to lock the starting numbers, so you can then fill in your own and check them.
- Give me a hint highlights one cell and explains why its number is certain. Press “Fill in” to add it.
- Check my numbers marks any mistakes in red. Solve fills in everything.
The rules of sudoku
Fill the 9×9 grid so that every row, every column and every 3×3 box contains the numbers 1 to 9 exactly once. A proper puzzle has only one solution, which can always be reached by logic.
Solving techniques the hints use
- Naked single: a cell where only one number fits, because the other eight already appear in its row, column or box.
- Hidden single: a number that can only go in one cell of a row, column or box, even if that cell has other options.
Easy and medium puzzles can usually be solved with these two alone. Harder puzzles need advanced techniques (pairs, pointing, X-wings); when no simple step is left, the hint gives you a number from the solution so you can keep going.
Works for daily sudoku puzzles
Use it with any standard 9×9 sudoku: the NYT easy, medium and hard puzzles, newspaper sudoku, apps or books. It doesn’t publish any puzzle; you enter the one you’re playing. This site is independent and not affiliated with The New York Times or any puzzle publisher.
Frequently asked questions
Can every sudoku be solved?
A correctly entered puzzle can. If the solver finds no solution, a number was probably entered in the wrong cell; the solver shows repeated numbers in red.
What if a puzzle has more than one solution?
The solver still finds one and tells you the puzzle isn’t unique. Published puzzles normally have exactly one solution.
Is my puzzle saved or uploaded?
No. Everything runs in your browser.