Sudoku Techniques
Master these patterns to solve harder puzzles.
Naked Pairs
Learn how to spot two cells in a group that share exactly the same two candidates.
Hidden Pairs
Discover candidates that are hiding within other pencil marks to eliminate noise.
X-Wing
A powerful technique that uses intersecting rows and columns to eliminate candidates.
Swordfish
An extension of the X-Wing pattern that uses three rows and three columns.