The Naked Triple Technique in Sudoku
The Naked Triple is the Naked Pair scaled up by one. When three cells in a unit, between them, contain only the same three candidates, those three digits belong to those cells — and can be cleared from everywhere else in the unit. The clever part: each cell need not show all three digits.
How to use a Naked Triple, step by step
- Work from full pencil marks.
- Find three cells in one unit whose candidates, combined, use only three different digits.
- Each cell may show two or three of them — what matters is the union is exactly three digits.
- Those three digits are locked to the three cells.
- Remove all three from every other cell in the unit, then look for singles.
What is a Naked Triple?
A Naked Triple is three cells in a row, column or box whose candidates together total just three digits — for example {2,5}, {5,8} and {2,8}. No cell needs all three; the combination does. Those three digits fill the three cells between them, so they leave every other cell in the unit. It extends the Naked Pair, and the same logic continues to quads.
How to spot a Naked Triple
Look for clusters of cells in a unit that share a small set of candidates, then test whether any three of them use only three digits in total. It is easiest after Naked and Hidden Pairs have tidied the grid. Keep candidates accurate — a stale mark hides triples. See the full order of play in tips & strategy.
Naked Triples in Sudoku: FAQ
What is a Naked Triple in Sudoku?
A Naked Triple is three cells in one unit whose candidates together use only three different digits. Those three digits are confined to the three cells, so they can be removed from every other cell in the row, column or box.
Do all three cells need the same three candidates?
No. Each cell can show two or three of the digits — what matters is that the three cells combined contain exactly three distinct candidates, such as {2,5}, {5,8} and {2,8}.
When should you use a Naked Triple?
On Hard and Expert grids after singles and pairs have been worked. Triples are easiest to find once Naked and Hidden Pairs have already thinned out the candidates.