Hidden Pair in Sudoku: How to Spot It
Learn how Hidden Pairs work in Sudoku, why they are harder to see than Naked Pairs, and how to clean up candidates.
Visual example
Hidden Pair: two numbers hide inside two cells
Candidates 2 and 7 can only go in the two blue cells, so the extra candidates there are removed.
Quick answer
Hidden Pair
A Hidden Pair in Sudoku is when two candidates appear only in the same two cells of a row, column, or box. Those two cells must contain those two numbers, so all other candidates can be removed from those cells.
Recognition rules
How to spot it
- Choose one row, column, or box.
- Pick two numbers and check where each can appear.
- If both numbers are limited to the same two cells, they form a Hidden Pair.
- Remove all other candidates from those two cells.
What is a Hidden Pair?
A Hidden Pair happens when two numbers can only fit in the same two cells of a row, column, or box. The pair is “hidden” because those cells may also contain other candidates.
When to look for it
Look for Hidden Pairs when a unit feels crowded and obvious eliminations are not available. Instead of scanning cells, scan where each number can go.
Why the cleanup works
If 2 and 7 can only appear in two cells in a unit, those two cells must eventually contain 2 and 7. Any other candidates in those cells are impossible and can be removed.
FAQ
What is a Hidden Pair in Sudoku?
A Hidden Pair is two numbers that can only go in the same two cells within a row, column, or box.
How is Hidden Pair different from Naked Pair?
A Naked Pair is visible as two identical two-candidate cells. A Hidden Pair may be inside cells with extra candidates, so you find it by tracking positions for two numbers.
What do you eliminate with a Hidden Pair?
You remove all other candidates from the two pair cells.
Is Hidden Pair harder than Naked Pair?
Usually yes, because the pattern is hidden among extra candidates instead of appearing as two clean two-candidate cells.
Practice this technique in Sudoku Coach
Read the pattern, then practice it step by step with guided hints that explain why the move works.
Related Sudoku techniques
Naked Pair in Sudoku: How to Spot It
Learn how Naked Pairs work in Sudoku, when to look for them, and how to remove candidates safely.
Hidden Single in Sudoku: How to Spot It
Learn the Hidden Single Sudoku technique: when a number has only one possible position in a row, column, or box.