Naked Triple sudoku technique

Three cells in a unit form a naked triple when, between them, they hold only three distinct candidates. The cells do not need to show all three digits each — lists like 1-4, 4-9 and 1-9 qualify just as well as three full 1-4-9 cells. However the digits distribute, those three cells will consume those three digits, so the rest of the unit can be swept clean of them.

How to find a naked triple

1. Pencil-mark a stubborn unit completely.
2. Hunt for three cells whose combined candidates form a set of exactly three digits.
3. Remove those three digits from every other cell in the unit.
4. Re-examine the unit — triples usually break the logjam that pairs could not.

The pattern on the grid

Worked example

The cells r7c1, r7c2, r7c3 form a naked triple on {2, 3, 6}. Those digits are consumed inside the set however they distribute, so the shared unit sweeps them out everywhere else: r8c3 loses 23, r9c1 loses 3, r9c3 loses 3. Check the pencil marks in the diagram — every elimination is verifiable by eye.

When it fails

Four distinct digits across the three cells means no triple, full stop. And remember the count is over the union: 1-4, 4-9, 1-9 works precisely because the union stays at three.

Puzzles that need it

These grids come from rated games on this site — our solver confirmed that naked triple was part of the shortest solving path for each one.

Every string is the standard 81-character format (0 = empty) — paste it into any solver to verify the rating and the solving path yourself. Want to try one under the clock? Play a free puzzle — no account needed — or create an account to train specific difficulty tiers.

Related techniques

• Naked Pair
• Hidden Pair
• Swordfish

All solving techniques