Good Sudoku by Zach Gage

Select a difficulty or start the daily challenge to begin a new puzzle. Fill the grid so each row, column, and 3x3 box contains the numbers 1 through 9 without repeats. Enable notes to mark candidate numbers and let auto pencil marks update as you place digits. Tap hint to learn a specific solving technique when you are stuck, from singles to advanced patterns. Use smart validation and undo to correct mistakes and refine your logic as you go. Try speed modes or pursue perfect solves to build your stats and streaks over time.