Up to now, every basic technique worked inside a single unit. One row, one column or one box, and you never stepped outside it.
Pointing Pairs change register. For the first time you are going to read a box and act on a row. That shift in dimension is what makes them so effective, and it is also why many solvers never see them.
How a box lays down the law to a row or a column, the Domino33 method for spotting the pattern in seconds, and why this technique is the exact mirror of Box Reduction.
🎬 The Domino33 video on Pointing Pairs
Here is the full tutorial, with worked examples and the search method.
▶ English audio track and English subtitles: pick either from the ⚙️ icon.
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▶ Subscribe for freePart 1
The box speaks to the row
The principle fits in one sentence, and it follows straight from the rules of the game:
If, inside a box, a digit can only go into cells that all sit on the same row, then that digit will necessarily occupy that row within the box. It is therefore impossible in the rest of the row, outside the box.
The same reasoning works with a column. Two or three aligned cells are enough, hence the names Pointing Pair and Pointing Triple. The word "pointing" says exactly what happens: the box points in one direction, and that direction becomes forbidden elsewhere.
A worked example
Here are the first three rows of a grid. Look at where the 7 can go inside the top-left box:
Box 1 is highlighted · shaded cells are digits already placed
Inside that box the 7 has only two possible locations, and both of them are on the first row. Wherever the box's 7 finally lands, it will be on row 1.
Consequence: row 1's 7 is already consumed by the box. It becomes impossible in the whole rest of the row.
The 7 is eliminated from columns 4, 6 and 7 of row 1
Three candidates fall at once, without a single digit being placed. And you still have no idea which exact cell the 7 will end up in. You do not need to: knowing where it cannot go is more than enough.
Many solvers constantly hunt for where to place a digit. Pointing Pairs ask the opposite: where can this digit no longer go? That switch of viewpoint is the real lesson of this technique.
Part 2
Pair, triple, row or column
The pattern comes in four variants, and all of them work in exactly the same way:
- Pointing Pair on a row: 2 cells aligned horizontally in the box
- Pointing Pair on a column: 2 cells aligned vertically in the box
- Pointing Triple on a row: the 3 cells of one band of the box
- Pointing Triple on a column: the 3 cells of one stack of the box
The digit must be impossible everywhere else in the box. If even one possible location remains on another row of the box, the pattern collapses and no elimination is allowed.
Part 3
The search method
Step 1, Work box by box
Take one box and finish it before moving on. Start with boxes holding 4 to 6 digits already placed: full enough for candidates to be scarce, empty enough for something to still be there.
Step 2, Digit by digit, list the locations
For each digit still missing from the box, spot the cells where it is still a candidate. It is the same counting work as for hidden pairs, and it pays off once again here.
Step 3, Keep only 2 or 3 locations
A digit present in 4 cells or more of the box cannot form a Pointing Pair, barring a rare coincidence. Focus on the ones with only 2 or 3 possible locations.
Step 4, Check the alignment, then eliminate
Are those locations all on the same row, or all on the same column? If so, remove the digit from that row or column, outside the box. The cells inside the box are left untouched.
Do not read the candidates cell by cell. Scan the box band by band, looking for a digit that appears on only one of the three bands. The eye catches that alignment far faster than digit-by-digit reading.
🎬 See the method in action
In the video several examples are worked through on real grids, with the search method laid out step by step.
Exercise
Your turn
Here is a map of the possible locations of the 2. It contains a Pointing Pair.
Look for a box whose 2s are all lined up on the same row.
Part 4
Practice quiz
Four questions to check what you have learned. Good luck!
❓ Frequently asked questions
A Pointing Pair occurs when a digit can only go into two cells of a box, and those two cells are aligned on the same row or the same column. That digit will therefore occupy that row or column inside the box, which lets you eliminate it from the rest of the row or column, outside the box.
Only in the row or column concerned, and only outside the box. The cells of the box itself are untouched: you still do not know which of the two will take the digit.
The direction of reading changes. The Pointing Pair reads the box and eliminates in the row. Box Reduction reads the row and eliminates in the box. Both describe the same box-line interaction, taken in each direction.
No. Three aligned cells inside a box form a Pointing Triple, and the reasoning is identical. The only condition that matters is that the digit is impossible everywhere else in the box.
📋 Summary
Pointing Pairs essentials
- Direction of reading: you read the box, you act on the row or column
- Setup: inside a box, a digit confined to 2 or 3 aligned cells
- Action: eliminate that digit from the rest of the row or column, outside the box
- Condition: the digit must be impossible everywhere else in the box
- Variants: pair or triple, on a row or on a column
- Mirror technique: Box Reduction, which reads the row and acts on the box
With Pointing Pairs and Box Reduction, you now hold all six basic techniques. They form the foundation every advanced technique is built on, starting with the X-Wing, which applies this same alignment reasoning to two rows at once.
📘 Go further with the Domino33 books
Pointing Pairs and every other technique on this site are covered step by step in the Domino33 memento, available in English.
