PIENSALIA / SUDOKU EDUCATION
Naked Pairs in Sudoku
A Naked Pair reserves two candidates in two cells of the same unit.
Level: Learn how Naked Pairs reserve two candidates in a Sudoku unit and remove them from every other cell in that unit.
Prerequisites
Know the three Sudoku rules and keep candidates consistent across each row, column, and 3 × 3 box.
How to apply it
- Scan the relevant units and write only legal candidates.
- Compare the positions or candidates described by the technique.
- Make one justified placement or elimination.
- Update related notes and rescan for new singles.
Worked example
If two cells in a row are both {2, 8}, no other cell in that row may keep 2 or 8 as a candidate.
Common mistakes
- Guessing before checking every related unit.
- Leaving stale candidates after a placement.
- Applying a pattern without verifying all of its positions.
When to use it
Use pairs after singles when a unit has candidates but no immediate placement.
Practice Sudoku
Apply this technique in a free puzzle without an account.