Select a logic variant or design a custom sandbox to start your focus training.
Standard 9×9 grid. Fill cells so every row, column, and 3×3 box contains digits 1 to 9 exactly once.
Classic rules plus cage groupings with math sum clues. Digits cannot repeat within a cage constraint.
Classic rules plus specialized grid layouts: X-Sudoku diagonals, Anti-Knight movements, Thermo, or Arrow constraints.
Enter your own board strings, cage definitions, or constraints manually to practice or analyze.
Race against the clock. Select a difficulty and solve the puzzle before time runs out.