Naked Triple
Three squares reserve three digits between them, so those digits can be crossed out elsewhere in the unit.
What it is
Look at three empty squares in one row, column or box. If their small notes, taken together, are only three digits, those three digits must stay in those three squares. You do not need to know their order. Cross the three digits out of every other square in that same unit.
How to spot it
Start with a unit that has several squares with two or three notes. Pick three squares and combine their notes. If you see only three different digits altogether, you have found the triple. Then erase those same digits from the other notes in the unit.
Worked example
One observation at a time: find the three-square digit pool, then see what it frees elsewhere in the unit.
Step 1 of 4: Look at one highlighted unit
Stay in this one row, column or box. Only the five prepared note squares matter for now.
Why it matters
A Naked Triple does not place a digit immediately. It clears notes, and that often exposes the next single. Think of it as a slightly larger Naked Pair: the same rule, with three squares instead of two.
Practise now
Solve a puzzle where this technique decides the game
Frequently asked questions
Do all three cells need all three candidates?
No, and this is the point most solvers get wrong. {1,4}, {4,7} and {1,7} is a perfectly valid triple. Only the union of the three cells must be exactly three digits.
How do I spot triples efficiently?
Focus on units containing three or more cells with two or three candidates, then test combinations. Cells with four or more candidates cannot be part of a triple.
Put it to use
Where you will meet it
Medium grids are where this move starts to matter: the obvious cells run out and the pattern takes over.
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