Naked Triple

Difficulty level: hard

A naked triple is three cells in one unit whose candidates, combined, contain only three distinct numbers. The cells don't all need every number: candidate sets like 25, 57, and 27 still form the triple 2-5-7.

Between them, the three cells must consume all three numbers, so those numbers can be removed from every other cell in the unit.

Triples are harder to see than pairs precisely because the candidate lists may be partial. Scan units where only four or five empty cells remain — triples are most common there.

Worked example

If the three highlighted cells hold only the candidates 2, 5 and 7 between them, those numbers are spoken for — erase 2, 5 and 7 from the rest of row 1.
1 (highlighted) (highlighted) (highlighted) 8 9

How to apply it

  1. Pencil-mark a unit fully.
  2. Look for three cells whose combined candidates total exactly three numbers.
  3. Erase those three numbers from all other cells of the unit.
  4. Follow up on any singles the eliminations reveal.

Practice it

The fastest way to internalize the naked triple is to use it. Play a free hard puzzle — the in-game hint system points out exactly this pattern when it appears, or browse the full technique library.