# Domain Addition

> **SUCCESS**
>
> **What is Domain Addition**
>
> "Domain Addition" is a feature that registers the domain of the website you want to measure and analyze in Ptengine. In particular, to use the "Cross-Domain feature" that accurately analyzes user behavior across multiple domains and subdomains, you need to register all target domains.

## **Key Features**

**Accurate Cross-Domain Measurement** User behavior across multiple domains is accurately measured as a continuous set of data without interruption.

**Centralized Management of Multiple Domains** You can manage a list of domains for websites to be analyzed and clearly define the measurement scope.

> **DANGER**
>
> **Important Notes**
>
> If there are any missing registrations, Ptengine's features will not work properly.
>
> In the Growth plan, the number of domain registrations is unlimited, but since data from different sites may be mixed, we recommend registering the minimum number of domains.

## Setup Instructions

You can register the domains you want to measure by following the steps below.

Log in to Ptengine Insight.

Click the **gear icon** in the upper right corner of the screen.

Follow the on-screen instructions and add the domain you want to measure in the domain settings screen.

> **SUCCESS**
>
> **Tips for Use**
>
> When measuring multiple domains, creating a [page group](/en/insight/setting/add-domain.md) makes it easier to view heatmaps.
>
> Detailed definitions of main domain, subdomain, and subdirectory can be found [in this article](/en/insight/setting/add-domain.md).


---

# Agent Instructions: Querying This Documentation

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

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://helps.ptengine.com/en/insight/setting/add-domain.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
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.