Number Grid PuzzleTrain your brain with number puzzles!

Number Grid Puzzle is a puzzle where you fill a 9-row by 9-column grid with numbers from 1 to 9. There are only three simple rules:

• ✅ Enter numbers 1 to 9 in the blank squares.
• ✅ Do not repeat the same number in any row or column.
• ✅ Numbers must not be repeated in any 3-row by 3-column block marked by bold lines.

This tool only provides puzzles with a single unique solution. You can enjoy solving without worrying about multiple answers.
(Often known internationally as Sudoku.)

1. Select a difficulty level
   Choose from "Beginner", "Easy", "Medium", or "Hard".
2. Click the "Generate Puzzle" button
   A new puzzle will be automatically displayed.
3. Enter numbers into the empty cells
   Use the on-screen input board to enter numbers from 1 to 9.
4. If you want to check your answer
   When you press the "Check" button, the incorrect and blank cells will turn red.
5. If you want to see the full answer
   Click the "Show Answer" button to reveal the entire solution.
   If shown, both puzzle and solution can be printed.
6. If you want a hint
   Click the "Hint" button to get the correct number for one of the empty cells.
   Hints are also read aloud by voice.
   Click the "Hint/Lines" button to highlight the row and column of the selected cell.
7. If you want to use Notes mode
   Click the "Notes" button to turn on Notes mode, which lets you write small candidate numbers in a cell.
   While Notes mode is active, pressing a number button will add it as a note instead of a final answer.
   Click the "Notes" button again to turn off Notes mode and return to normal input.
   When you confirm a number in a cell, any notes in that cell will be automatically cleared.
8. If you want to save and resume later
   Click "Save" to record your current progress.
   Click "Load" to resume from where you left off.
9. If you want to undo
   Click "Undo" to go back one step.
10. If you want to print
    Click "PDF / Print" to print out the puzzle.
    If the solution is visible, both the puzzle and answer will be printed.
11. If you want to delete saved data
    Click "Delete Save" to remove the saved progress.