Beat their time. Climb the ranks.
One board. One clock. Whoever finishes clean wins.
Learn the techniques. Beat their time.
Every difficulty tier is defined by the hardest technique its puzzles require — from a first naked single to a full Y-Wing.
- Naked SingleOnly one digit can possibly go in this cell.Easy
- Hidden SingleA digit that only fits in one cell of a row, column, or box — even if that cell still has other candidates.Medium
- Naked PairTwo cells in a unit that share the exact same two candidates lock those digits down.Hard
- X-WingA digit trapped in the same two columns across two rows forms a rectangle you can eliminate around.Expert
- Y-WingThree bivalue cells linked by two shared digits eliminate a third digit from their common neighbors.Expert
Questions, answered
A Sudoku site built around racing, not just solving. Instead of a lone timer, you race a recorded solve — a Ghost Run — from another player on the same puzzle. Beat their Effective Time and you win.