Difficulty
Easy
Sudoku technique guide
Pointing Pair
When the easy moves slow down, one clear pattern can make the next step feel possible again. Pointing Pair 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
Locked candidates
Purpose
Removes candidates
Typical puzzle stage
Early to middle
Frequency
Common
Prerequisites
Candidate marks and box scanning
Why this technique matters
Pointing Pairs are a clean bridge from placing answers to removing possibilities. They show that a 3x3 box can control the rest of a row or column.
The idea in plain English
If all possible positions for one digit inside a box lie on the same row or column, that digit cannot appear elsewhere along that row or column outside the box.
How to recognise it
Look for two or three matching candidate marks lined up inside one box. The line they share is the important clue.
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 one digit inside a 3x3 box.
Then. Find every candidate position for that digit in the box.
Next. Check whether they all sit in one row or one column.
Finally. Remove that digit from other cells in the same line outside the box.
When it usually appears
Look for it when a box has a digit restricted to a line, especially after singles have made a box more constrained.
Common traps
These are easy places to get turned around. They are useful checks, not signs that you are doing badly.
- Eliminating inside the box. The removal happens outside the box, along the shared row or column.
- Using only two candidates as proof without checking for a third candidate elsewhere in the box.
Frequently asked questions
Does it have to be exactly two candidates?
No. A pointing pair commonly has two, but three aligned candidates can create the same elimination.
What is the reverse pattern?
Box-Line Reduction: a row or column restricts a digit to one box, so candidates are removed from the rest of that box.
Quick takeaway
- A Pointing Pair belongs to the locked candidates family.
- Its purpose is to remove candidates.
- Look for a complete pattern, not one that only nearly fits.
- It is most useful early to middle.
- Once you make the deduction, return to the simpler scans.