Sudoku strategy

Naked Singles Sudoku Strategy

Beginner technique Beginner

A naked single is an empty cell with only one legal candidate left after checking its row, column, and box.

How to use it

  1. Choose one empty cell.
  2. Remove every digit already used in the same row, column, and 3x3 box.
  3. If one digit remains, place it.
  4. Repeat after every placement because new singles often appear immediately.
Practice: Start with an Easy puzzle and enable auto-update candidates to see naked singles appear as you solve.

Practice this strategy

Use the interactive solver to practice this technique on a fresh puzzle. If you get stuck, the Human Solve mode can show the next logical step.

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