Naked Pair sudoku technique

When two cells in the same unit hold exactly the same two candidates — say 2 and 7, and nothing else — those two digits are spoken for. One cell will take the 2 and the other the 7; you may not know which way round yet, but no other cell in that unit can have either. Erasing 2 and 7 from the rest of the unit often cracks it open.

How to find a naked pair

1. Write pencil marks for a unit that refuses to move.
2. Look for two cells whose candidate lists are identical and exactly two digits long.
3. Remove both digits from every other cell in that unit.
4. Check what the eliminations reveal — a naked pair very often exposes a single in the next breath.

The pattern on the grid

Worked example

The cells r3c4, r3c9 form a naked pair on {1, 4}. Those digits are consumed inside the set however they distribute, so the shared unit sweeps them out everywhere else: r3c1 loses 14, r3c5 loses 14, r3c6 loses 1. Check the pencil marks in the diagram — every elimination is verifiable by eye.

When it fails

The pair must live in one shared unit. Cells r5c2 and r6c6 with identical candidates share nothing and prove nothing — geometry first, candidates second.

Puzzles that need it

These grids come from rated games on this site — our solver confirmed that naked pair 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

• Hidden Pair
• Naked Triple
• X-Wing

All solving techniques