Online Sudoku Solver & Game - Play Free Sudoku Puzzles Daily

Train your brain with Sudoku Master. Enjoy infinite generated boards across Easy, Medium, and Hard difficulties, featuring pencil draft notes, auto-validation, move history, and timers.

1. Step 1: Select your difficulty tier and click cells to input numbers from 1 to 9.
2. Step 2: Toggle Draft/Notes mode to place candidate numbers inside empty cell spaces.
3. Step 3: Resolve all rows, columns, and 3x3 square blocks without repeating any digits.

How does the notes/pencil feature work?

Toggling the "Pencil" mode lets you insert small candidate numbers inside a cell, which are automatically cleared when a solid digit is set.

Are the Sudoku boards mathematically valid?

Yes, every board is generated using standard back-tracking sudoku algorithms to ensure a single unique mathematical solution.

Can I check my progress or undo a mistake?

Absolutely! You can check for immediate errors, erase individual cells, or use the Undo/Redo history buttons anytime.