Naked Pair
Two cells in a unit with the same two candidates. Those two digits are locked into those cells, so the rest of the unit drops them.
Intermediate sudoku technique
What it is
A naked pair is two empty cells inside a single unit (row, column, or box) whose candidate sets are identical and contain exactly two digits. Since those two digits MUST occupy those two cells in some order, no other cell in that unit can hold either digit. Naked pairs are the first technique to require pencil-mark tracking — you can't reliably spot them without writing candidates in each cell. They're the bedrock of intermediate solving.
Want the full theory?
The Naked Pair guide on Sudoku247Wiki walks through the logic step by step, with worked examples, diagrams and FAQs.
Read the full Naked Pair guide →Try it
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