Online Sudoku Solver

This online Sudoku solver is unique on the web. It not only gives the solution to each valid Sudoku puzzle instantly, but also explains the techniques and logic behind each step and how the digit to be filled in each empty cell is determined. Because of this, it becomes a great tool to learn Sudoku solving techniques through numerous examples.

To use our Sudoku solver, just enter your valid Sudoku puzzle in the blank grid above. If you want a step by step solution with an explanation for each step, press the "Step by Step Solution" button, and it will bring up our smart Sudoku solver to give you the solution with step by step explanations. If you just want a solution for your puzzle, press the "Solution Only" button, and it will give you the solution instantly.

You may also use our Sudoku solver to check whether your Sudoku puzzle is valid or not. If your puzzle is not valid (having no solution or more than one solution), you will get an alert from our Sudoku solver when pressing the "Solution Only" button or the "Step by Step Solution" button.