Sudoku
Find the quiet order in a grid of numbers. Nine digits, endless possibilities.
How to play Sudoku
- Fill every empty square with a digit from 1 to 9.
- Each row, column and outlined 3 × 3 box must contain each digit exactly once.
- The starting numbers are fixed. Use pencil notes to keep track of possibilities.
Make your move
Select a square, then use the number pad or your keyboard. Turn on Pencil notes to record candidates. Arrow keys move the selection; Backspace clears it.
Find your level
Start with Beginner or Easy to learn the rules, choose Medium for a steady challenge, or explore Hard and Expert when available. Ratings use each game’s solver effort and clue structure. Some size and difficulty combinations are unavailable until they can be generated reliably.
Every new puzzle is generated on your device and checked for a unique solution. You can pause, get a hint, or come back later. Your progress stays in this browser.
A little more to know
Does every Sudoku have one answer?+
Yes. The generator counts solutions before accepting a puzzle. Every published Sudoku has exactly one solution.
What do pencil notes do?+
Notes let you mark possible digits without committing an answer. They are saved with your game and included in undo and redo.
Can I share this exact puzzle?+
Yes. Use Share to copy a link with the puzzle’s ID. The same version, size, difficulty and seed recreate the same starting puzzle. Your answers are not shared.
Is my progress saved?+
Your puzzle, timer, notes and undo history save automatically in this browser when storage is available. Private browsing, clearing website data or changing devices may remove access to your save.