About Sudoku Zen
Sudoku Zen generates a fresh puzzle every time you play, and every puzzle has exactly one solution. Fill the 9×9 grid so that each row, each column and each 3×3 box contains the digits 1 to 9 exactly once.
The interface stays out of your way: matching digits light up when you select a cell, conflicting entries turn red, and pencil notes let you track candidates. Easy puzzles are great for a coffee break, while Hard puzzles call for real deduction.
How to play
- Select an empty cell by tapping or with the arrow keys.
- Enter a digit from the number pad or your keyboard.
- Switch on Notes to pencil in several candidate digits.
- Complete the grid with no conflicts to solve the puzzle.
Tips and strategy
- Start with rows, columns and boxes that are already mostly filled.
- If a digit can only go in one cell of a box, place it, even if that cell has other candidates.
- Use notes on Hard puzzles. Writing candidates down reveals pairs and hidden singles.
Frequently asked questions
Are the puzzles unique?
Yes. Each grid is generated on your device and checked to make sure it has exactly one solution.
How is my time recorded?
The timer starts when the puzzle appears. Your fastest solved time is saved on your device.
What does a hint do?
A hint fills one correct digit into the selected or a random empty cell. Hints add 30 seconds to your time.
