> For the complete documentation index, see [llms.txt](https://helps.ptengine.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://helps.ptengine.com/en/insight/setting/add-domain.md).

# 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).