Naked Single

A Naked Single is the simplest pencilmark technique. When a cell has only one candidate remaining (after all eliminations from its row, column, and block), that candidate must be the solution.

Technique

1. Enable pencilmarks to see all candidates for each cell.
2. Look for any cell that has only one candidate remaining.
3. That candidate is the solution for the cell.

Tips

• Pencilmarks are essential for spotting Naked Singles.
• After placing any digit, check its row, column, and block for new Naked Singles.
• In easy puzzles, Naked Singles can chain together quickly.