Minimal Sudoku
Pointing Pairs technique in Sudoku
Learn Section

Pointing Pairs & Triples

When Box Candidates Point to Line Eliminations

By Minimal Sudoku TeamLast updated:

Pointing Pairs and Pointing Triples are elegant techniques that exploit the interaction between boxes and lines. When a candidate within a box is confined to a single row or column, it "points" to eliminations outside the box.

⚡Quick Summary
  • What: A candidate in a box appears only in one row or column
  • Result: Eliminate that candidate from the rest of the row/column outside the box
  • Pointing Pair: Candidate in exactly 2 cells on the line
  • Pointing Triple: Candidate in exactly 3 cells on the line
  • Difficulty: Intermediate — works great with Snyder Notation

The Concept

Every 3×3 box must contain each digit 1-9. If we look at where a specific digit can go within a box, sometimes all possible cells fall on the same row or column.

When this happens, we know the digit will definitely be placed somewhere on that line within this box. This means it cannot appear elsewhere on the same line — giving us eliminations outside the box.

Pointing Pair visualization:
Box 1:              Row extends beyond box:
┌───────────┐       
│ . │ . │ . │       
│───│───│───│       
│[5]│[5]│ . │  →→→  │ ✗ │ ✗ │ ✗ │ ✗ │ ✗ │ ✗ │
│───│───│───│       
│ . │ . │ . │       (eliminate 5 from rest of row)
└───────────┘

The Golden Rule

👉 Pointing Pair/Triple Rule
If a candidate appears in only one row (or column) within a box, eliminate that candidate from all other cells in that row (or column) outside the box.

How to Find Pointing Pairs

1

Pick a box

Choose any 3×3 box to analyze.
2

Pick a candidate

Choose a digit (1-9) that hasn't been placed in this box yet.
3

Find all possible cells

Identify every cell in the box where this candidate could go.
4

Check alignment

Are all possible cells in the same row? Or the same column? If yes, you have a Pointing Pair (2 cells) or Pointing Triple (3 cells).
5

Eliminate outside the box

Remove the candidate from all other cells in that row or column (the cells outside this box).

Practical Example

Pointing Pair on Digit 5

Pointing Pair example with digit 5

In the top-left box (Box 1), let's look for where digit 5 can go:

  • R1C1: 5 appears in column 1 → eliminated
  • R1C2: 5 appears in row 1 → eliminated
  • R1C3: 5 appears in row 1 → eliminated
  • R2C1: No conflicts → possible
  • R2C2: No conflicts → possible
  • R2C3: 5 appears in column 3 → eliminated
  • R3C1-C3: Various conflicts → eliminated

The candidate 5 can only go in R2C1 or R2C2 — both in row 2!

Elimination
Eliminate 5 from all other cells in row 2 (R2C4 through R2C9). The 5 for row 2 must come from Box 1.

Why It Works

The logic is straightforward:

Works for Triples Too
If the candidate appears in 3 cells all on the same line within the box, the logic is identical. It's called a Pointing Triple instead of Pointing Pair.

Pointing vs Claiming Pairs

Pointing Pairs and Claiming Pairs are mirror techniques:

👉 Pointing Pair

Start in a box, find candidates aligned on a line.

Eliminate from the line (outside the box).

📍 Claiming Pair

Start on a line, find candidates confined to one box.

Eliminate from the box (outside the line).

Together, they form the "Locked Candidates" family — techniques that use the intersection of boxes and lines.

Claiming PairsIntermediate

Claiming Pairs

The reverse technique: when line candidates are confined to one box.

Detection Tips

Perfect for Snyder Notation
Snyder Notation naturally reveals Pointing Pairs. When you mark a candidate in exactly two cells of a box and they're on the same row or column, you've found one!
Scan Boxes Systematically
For each box, check each missing digit. Ask: "Are all possible cells for this digit on one line?" This systematic approach ensures you don't miss any.
Look for Nearly-Complete Lines
If a row or column is almost full (6-7 cells filled), check the boxes it passes through. Candidates in those boxes often form Pointing Pairs.

Related Techniques

Locked Candidates

📍Claiming Pairs✏️Snyder Notation

Related Intermediate Techniques

👥Naked Pairs🔍Hidden Pairs✈️X-Wing