Sudoku Flow
Sudoku technique lessons / Naked Single
Lesson 3

Naked Single

The rule

A cell with only one candidate left must hold that number.

Step by step

  1. Look at this row. It rules out 3, 4, 8 for this cell.
  2. Now check this column. It also rules out 2, 7, 9.
  3. The box also contains 1, 6, so remove those candidates from this cell.
  4. All other candidates are eliminated! Only 5 can go in this cell.
Read the full lesson, with more examples →Watch on YouTube

Try it on more boards

Each board is a real puzzle from our app, at a moment where Naked Single applies. Find the step yourself, or tap Hint and the app's own hint walks you through it.

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Sudoku Flow is made by Rubigo Games, the developer of the Sudoku app recommended on this site.