Sudoku Solving Techniques

Master Sudoku one pattern at a time. Each guide explains a technique with a worked grid example, when to reach for it, and what to try next. Put them into practice with the free daily puzzles — the in-game hints reference these exact techniques.

• Naked Single easy

  The most fundamental Sudoku technique: when a cell has only one possible candidate left, that number must go there. Learn to spot naked singles fast.

• Hidden Single medium

  A hidden single is a number with only one possible home inside a row, column, or box — even when that cell has other candidates. Here is how to find them.

• Naked Pair hard

  When two cells in a unit share the same two candidates, those numbers belong to them alone — and can be erased from every other cell in the unit.

• Pointing Pair hard

  When a number's only spots in a box line up in one row or column, that number can be eliminated from the rest of the row or column outside the box.

• X-Wing expert

  The X-Wing spots a number locked into two columns across two rows, forming a rectangle that eliminates the number everywhere else in those columns.

• Hidden Pair hard

  When two numbers can only live in the same two cells of a unit, those cells belong to them — every other candidate in those cells can be erased.

• Naked Triple hard

  Three cells in a unit that share the same three candidates lock those numbers up — and clear them from the rest of the row, column, or box.

• Box-Line Reduction hard

  If a number's only possible cells in a row or column all sit inside one box, the number can be erased from the rest of that box.

• Swordfish expert

  The Swordfish extends the X-Wing to three rows and three columns, locking a number into a 3×3 lattice and clearing it from the rest of the columns.

• XY-Wing expert

  Three two-candidate cells form a pivot-and-pincers pattern that proves one number impossible wherever both pincers reach.