sudokly
Expert · Typical solve: 25 to 60 minutes

Expert Sudoku, Free Online

XY-wing, swordfish and chain logic.

EasyMediumHardExpertEvil
Expert00:00✕ 0
About expert

What expert sudoku feels like.

Expert sudoku gives you 25 to 27 clues. Most cells will sit at three or four candidates for a long stretch, and you will need XY-wings, swordfish or coloring to crack them. Patience pays.

Typical solve time
25 to 60 minutes
Who it's for
Serious solvers comfortable with intermediate techniques.
Techniques
XY-wing, Swordfish, Simple coloring, Unique rectangle

Expert sudoku FAQ

Is expert sudoku always logical?

Yes. Every Sudokly expert sudoku is verified solvable using techniques up through XY-wing and swordfish. No guessing required.

How long should expert sudoku take?

Most experienced solvers finish expert sudoku in 25 to 60 minutes. Do not be surprised if you spend ten minutes scanning before finding a move. That is normal for expert.

What is the difference between hard and expert sudoku?

Hard puzzles are typically solvable with techniques up through X-wing. Expert routinely requires XY-wing, swordfish or coloring to make progress.

When does pencil marking become essential?

At expert level, pencil marks are mandatory. You will not find chain techniques without seeing the full candidate set in every empty cell.

Are expert puzzles unique?

Yes. Uniqueness is verified by our solver during generation. If a puzzle has two solutions, it is discarded before it reaches the site.