How to play

Fill each row, column and 3 × 3 box with 1–9, without repeats. Keep the given digits.

Choose a difficulty

Difficulty reflects solving techniques, not completion time. Progress is saved in this browser.

Find cells with one possible digit.

Find a digit’s only place in a row, column or box.

Eliminate candidates using rows, columns and boxes together.

Use pairs, singles and locked candidates.