Naked Single

A cell has only one candidate left after eliminating peers.

Learn the Naked Single Sudoku technique: a cell whose row, column, and box leave just one possible digit. Play and learn free.

How to use it

  1. Pick an empty cell. Choose any empty cell and look at its row, column, and box.
  2. Eliminate seen digits. Cross off every digit that already appears in that cell’s row, column, or box.
  3. One candidate remains. If exactly one digit survives, it is a Naked Single — place it with confidence.
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