Difficulty
Medium
Sudoku technique guide
Naked Triple
When the easy moves slow down, one clear pattern can make the next step feel possible again. Naked Triple helps you spot what the grid is already telling you.
By the end, you will know what to notice, how the idea works and when it is worth using.
At a glance
Technique family
Naked subsets
Purpose
Removes candidates
Typical puzzle stage
Middle
Frequency
Occasional
Prerequisites
Naked Pairs and candidate marks
Why this technique matters
Naked Triples build on the pair idea and teach you to group cells by a shared set of digits rather than by identical notes.
The idea in plain English
A Naked Triple is three cells in one unit whose combined candidates are exactly three digits. Those digits must fill those three cells, so they can be removed elsewhere in the unit.
How to recognise it
The three cells may not look identical. For example, {1,4}, {1,7} and {4,7} still form a triple.
Pause when you see this shape. You do not have to force it; just check whether the pattern is complete.
How the logic unfolds
Think of this as a short conversation with the grid. Take one check at a time, and let each answer tell you what to inspect next.
Start by. Choose a unit with several cells holding two or three candidates.
Then. Find three cells whose combined candidate set contains only three digits.
Next. Check that each of those digits appears only within the three chosen cells for this pattern.
Finally. Remove the three digits from all other cells in the unit.
When it usually appears
Try this when pair scans do not help and one unit contains compact two- and three-candidate groups.
Common traps
These are easy places to get turned around. They are useful checks, not signs that you are doing badly.
- Including a fourth digit. Then it is not a Naked Triple and no elimination follows.
- Forgetting that all three cells must share the same unit.
Frequently asked questions
Can one cell have only two candidates?
Yes. A triple may be made from a mixture of two- and three-candidate cells.
Why is it harder than a pair?
You must compare the combined set, not just match two identical cells.
Quick takeaway
- A Naked Triple belongs to the naked subsets family.
- Its purpose is to remove candidates.
- Look for a complete pattern, not one that only nearly fits.
- It is most useful middle.
- Once you make the deduction, return to the simpler scans.