Rows
Each horizontal row must contain 1, 2, 3, 4, 5, 6, 7, 8, and 9 once.
Rules
Sudoku Rules
The goal of Sudoku is to complete the grid so every row, every column, and every 3x3 box contains the digits 1 through 9 without repeats.
Columns
Each vertical column follows the same rule and cannot repeat a digit.
Boxes
Each 3x3 box must also contain every digit from 1 through 9 exactly once.
Frequently asked questions
Can a Sudoku row repeat a number?
No. Every row must contain the digits 1 through 9 exactly once.
Can I guess in Sudoku?
You can, but good Sudoku solving relies on logic. Notes and scanning usually reveal the next move.
What is a 3x3 box?
The 9x9 grid is split into nine smaller 3x3 boxes. Each box must also contain the digits 1 through 9.