How to play Sudoku
Fill each row, column and 3×3 box with the numbers 1–9, without repeats. Select a cell and use the number buttons or your keyboard. Given numbers cannot be changed.
Hints and checking
Choose Easy, Medium or Hard. Use Check to find mistakes and Hint to reveal a cell. Hints are limited by difficulty. Clear removes an entry from the selected editable cell.
Daily Sudoku and challenges
Daily Sudoku gives everyone on the same difficulty the same board for that date. A challenge link includes the board seed and difficulty; after completion it also includes your time to beat. Switching language preserves these challenge parameters.
Records on this device
Best times, completed games and daily streaks are saved locally in your browser. Clearing browser storage removes them. Ukrainian and English pages share the same records on this device.