> For the complete documentation index, see [llms.txt](https://docs.mediarithmics.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.mediarithmics.io/audience-and-activation/build-your-audiences/segment-reference/segment-capabilities/overlap.md).

# Overlap

The analysis that shows which segments share the most users with the one you are looking at.

## What it computes

An **overlap analysis** shows the similarities between segments. Run one on a segment and you get a bar chart of the **20 segments that share the most users** with it.

The segments are sorted by the percentage of shared users, calculated against the **total number of users in the current segment** - not against the other segment's size. That asymmetry is the thing to remember when reading the chart.

{% hint style="info" %}
**Why the direction matters.** A small segment can overlap a large one at 100% while the large one overlaps the small one at a few percent. Run the analysis from the segment whose audience you are trying to explain.
{% endhint %}

Hold the pointer over a bar to see the full name of the corresponding segment and the percentage of common users.

## It is a snapshot, not a live figure

The bar chart displays the data as it was **at the time the analysis was run**. The timestamp is shown in the top right corner of the chart. Press **Refresh** to recompute it.

## Running one

Click **Create Overlap Analysis** on the segment page. To filter the chart by label and decide what to do with the result, see [Overlap segments](/audience-and-activation/analyze-your-data/overlap-segments.md).

## Related pages

<table data-view="cards" data-search="false"><thead><tr><th></th><th></th><th data-hidden data-card-target data-type="content-ref"></th></tr></thead><tbody><tr><td><strong>Overlap segments</strong></td><td>What to do with the result.</td><td><a href="/audience-and-activation/analyze-your-data/overlap-segments.md">Overlap segments</a></td></tr><tr><td><strong>Compare segments</strong></td><td>The other way to relate two segments - dimension by dimension.</td><td><a href="/audience-and-activation/analyze-your-data/compare-segments.md">Compare segments</a></td></tr></tbody></table>


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation by asking a question.

Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET https://docs.mediarithmics.io/audience-and-activation/build-your-audiences/segment-reference/segment-capabilities/overlap.md?ask=<question>&goal=<user_goal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.