SudokumaxSudokumax
Lesson 25 min

Your First Sudoku Puzzle

Never solved a Sudoku before? Perfect. This guided walkthrough teaches you the three fundamental rules by having you solve real cells step by step. No prior knowledge needed.

The Three Rules of Sudoku

1. Rows

Every row must contain the digits 1 through 9, each exactly once.

2. Columns

Every column must contain the digits 1 through 9, each exactly once.

3. Boxes

Every 3×3 box must contain the digits 1 through 9, each exactly once.

1 / 5

Step 1: Complete a Row

Look at row 1 (the very top row). Eight of nine cells are already filled. Count which digit from 1 to 9 is missing — that is your answer!

Key Concept

Every row must contain the digits 1 through 9 exactly once. If only one cell is empty, you can figure out the missing digit by counting.

5
3
4
6
8
9
1
2
6
2
1
9
5
3
4
8
1
9
8
3
4
2
5
6
7
8
5
9
7
6
1
4
3
4
2
6
8
5
3
7
9
1
7
1
3
9
2
4
8
5
6
9
1
5
3
7
2
8
4
2
8
7
4
1
9
6
3
5
3
4
5
2
6
1
7
9

Click the highlighted target cell, then type the answer (or use the number pad on mobile).