START SOLVING
Play Sudoku
Select any empty square, choose a digit from 1 to 9, and fill the grid so every row, column and 3×3 box contains each digit once.
Use notes
Candidate notes help you track possible digits. Remove candidates as rows, columns and boxes reveal new information.
Avoid guessing
Every included puzzle is designed to be solved by logic. If stuck, scan for a cell or unit with only one possible digit.