---
title: "Hidden Pair: Two digits have just two places"
description: "If two digits can appear only in the same two cells of an area, they form a Hidden Pair. Other candidates can be removed from those two cells."
lang: "en"
canonical: "https://unisu-sudoku.app/en/sudoku-techniques/hidden-pair/"
---

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Core techniques

# Hidden Pair: Two digits have just two places

If two digits can appear only in the same two cells of an area, they form a Hidden Pair. Other candidates can be removed from those two cells.

![Unisu lesson on Hidden Pair, showing the explained grid](https://unisu-sudoku.app/_astro/en.n0Bpbk_z_Z2wo4Du.webp)

If two digits can appear only in the same two cells of an area, they form a Hidden Pair. Other candidates can be removed from those two cells.

## An example from the app

In row 7, the digits 3, 8 occur as candidates only in the 2 highlighted cells C7, H7. Those cells also contain other notes.

Those 2 digits need exactly those 2 cells. The extra candidates in those cells cannot be true. The removals happen inside the highlighted group.

These notes are therefore ruled out: H7: 7, 9.

The image shows the candidates relevant to this step. A note being hidden does not mean it has been logically eliminated.

## Practice the next step

This time the eliminations are inside the reserved cells, which is the key difference from a Naked Pair.

In the app, follow the reasoning in the matching lesson and try a task yourself. With a new puzzle, always start from its actual candidate state.

## Questions about Hidden Pair

### How do I recognize a Hidden Pair?

Two digits can occur only in the same two cells of an area. Those cells may also have other candidates.

### Which notes can I remove?

Other candidates within the two reserved cells. Keep the two reserved digits.

### Can a Hidden Pair occur in a box?

Yes. Examine a row, column or box. Within that area, the two digits must be restricted to the same two cells.

### How does it differ from Naked Pair?

Hidden Pair starts with two digits and their positions. Naked Pair starts with two cells containing exactly the same candidate pair.

### Why inspect the other cells too?

An extra position for either digit can invalidate the restriction. Looking only at the proposed pair is not enough.

## Keep practicing in Unisu

Download Unisu for iPhone or Android. Solve a puzzle or work through a guided lesson on the technique.

-   [Download on the App Store](https://apps.apple.com/us/app/id6775824061?l=en)
-   [Get it on Google Play](https://play.google.com/store/apps/details?id=app.unisu.sudoku&hl=en)

## Useful before this guide

### Hidden Single

[Read more: Hidden Single](https://unisu-sudoku.app/en/sudoku-techniques/hidden-single/)

### Sudoku pencil marks: track and update candidates

[Read more: Sudoku pencil marks: track and update candidates](https://unisu-sudoku.app/en/sudoku-techniques/pencil-marks/)

## Where to go next

Core techniques

Unisu · Oct 27, 2026

### [Hidden Triple: Three digits confined to three cells](https://unisu-sudoku.app/en/sudoku-techniques/hidden-triple/)

A Hidden Triple occurs when three digits have only three possible cells between them in a row, column or box. Extra candidates in those cells can be removed.

Unisu

### [Learn Sudoku: a path from rules to techniques – Unisu](https://unisu-sudoku.app/en/learn/)

Start with the rules, get comfortable with pencil marks and choose a technique for the situation you’re working on.

Download app

## Ready for a puzzle? Take a moment.

Download Unisu on your phone. Start a Sudoku or choose a lesson on the technique you want to understand.

-   [Download on the App Store](https://apps.apple.com/us/app/id6775824061?l=en)
-   [Get it on Google Play](https://play.google.com/store/apps/details?id=app.unisu.sudoku&hl=en)

![The daily challenge in Unisu](https://unisu-sudoku.app/_astro/en.C-sYR9hJ_1QwI9G.webp)

![A classic Sudoku game in Unisu](https://unisu-sudoku.app/_astro/en.C6DJ1kiE_2dRWDN.webp)