Medium Sudoku

Medium Sudoku adds hidden-single deductions to the basic rules. Every grid has one solution.

▶ Play Medium Sudoku

How to play Sudoku

Fill the 9×9 grid so every row, every column, and every 3×3 box contains the digits 1–9 exactly once. Tap a cell, then a number — or use Notes to pencil in candidates. There’s no guessing: every QZBrain puzzle is solvable by logic.

Frequently asked questions

How hard is medium Sudoku?

Medium puzzles need “hidden singles” (a number with only one possible home in a row, column, or box) in addition to the basics.

Can I select another puzzle?

Yes. Return to the game controls to change the difficulty, theme, or grid size.

Is there a daily mode?

Sudoku, Word Search, and Nonogram each include a daily puzzle and practice options.

QZBrain Focus includes adaptive memory, attention, number, and word games. Puzzle results are tracked separately. You can also read articles on brain training.