Back to Sudoku Rules
🧠 Sudoku Rules

📋 Naked Triples – Sudoku Technique

If three cells in a unit collectively hold only three candidates, remove those candidates from the other cells in that unit. Illustrated guide with common pitfalls and tips.

What Are Naked Triples?

A naked triple occurs when three cells in a row/column/box collectively hold only three candidates (e.g., {1,4,9}) with no extras. Those digits must occupy those three cells, so they can be removed from all other cells in the unit.

Step-by-Step Example

Step 1: Several 9 candidates along the top row
1) Candidate scan: the top row shows multiple 9 possibilities.
Step 2: Three cells form the {1,4,9} triple; clear others
2) Three cells form a naked triple (e.g., {1,4,9}); eliminate these digits from the remaining row cells.
Step 3: After eliminations, a 9 becomes a direct placement
3) After the cleanup, a direct placement appears: 9.

Where It Works

  • Any row,
  • Any column,
  • Any 3×3 box.

Common Mistakes

  • Confusing with a hidden triple (visible vs. hidden candidates).
  • The three cells having more than three candidates in total (then it isn’t “naked”).

Tips

  • Clear singles and naked pairs first; triples pop out more easily afterwards.
  • Once spotted, immediately clear those digits from the rest of the unit.
More Sudoku RulesAll RulesPlay Sudoku