Beginner

Naked Single

When one empty cell has exactly one candidate.

Explanation

Check the row, column, and box around an empty cell. If every other digit is blocked, the remaining candidate is forced.

Naked Single example Sudoku board 5 3 7 6 1 9 5 9 8 6 8 6 3 4 8 3 1 7 2 6 6 2 8 4 1 9 5 8 7 9
An example board where Naked Single applies

Practice tip

Use this to build confidence before moving into hidden singles.

Example steps

  1. Find an empty cell and list the missing digits.
  2. Use the row, column, and box to remove candidates.
  3. Only 5 remains, so the cell is forced.

Try this technique on a real puzzle.

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