Sudoku
Mistakes 0
Time 00:00
Best —
Select a cell, then type 1-9 (or use the pad). ✏️ toggles notes, ⌫ erases.
How to play
- Fill the 9x9 grid so every row, column, and 3x3 box contains the digits 1 to 9.
- Tap a cell, then type a number or use the on-screen number pad.
- Use notes (pencil marks) to jot down candidate numbers for a cell.
- The given numbers cannot change. Solve the whole grid to win.
Strategy & tips
- Scan for cells where only one number can possibly go, and fill those first.
- Work box by box, and row by row, looking for a digit that fits only one spot.
- Use pencil notes to track candidates, then eliminate them as you place numbers.
- Look for "naked pairs" — two cells in a unit that can only be the same two numbers.
- When stuck, switch to a different row, column, or box; a new angle often reveals a move.
FAQ
Does every puzzle have one solution?
Yes. Every board is generated with a unique solution, so it can always be solved by logic without guessing.
Is Sudoku free here?
Yes — it plays free in your browser with no download or sign-up, on desktop and mobile.
What are the difficulties?
Easy, Medium, and Hard, which differ by how many numbers are given at the start.
Does it track my time?
Yes. A timer runs while you solve, and your best time per difficulty is saved in your browser.