---
title: "Browser ID"
slug: "browser-id"
abstract: "Describes the browser ID and how to use it to find a guest in Sitecore Personalize."
---
# Browser ID

The browser ID is a [universally unique identifier (UUID)](https://en.wikipedia.org/wiki/Universally_unique_identifier) that Sitecore Personalize assigns to every user of your app. It associates sessions, events, and orders with the respective user.

## The browser ID in integrations using the Engage SDK

The Engage SDK automatically creates the browser ID. Then, the web browser stores the browser ID as a first-party cookie. The cookie is persisted until it expires or gets deleted.

You can use the [`Engage.getBrowserId()`](https://doc.sitecore.com/personalize/en/developers/api/stream-api/sitecore-engage-sdk-reference/functions/engage-getbrowserid.html "Engage.getBrowserId()") function to get the browser ID, then [find data about the associated user](https://doc.sitecore.com/personalize/en/developers/api/integrating-with-sitecore-personalize/understanding-integration-details/browser-id.html#UUID-405a29d9-69a3-8ace-b053-0e729d131ab8_section-idm4683430262585633192162002753 "The browser ID in Sitecore Personalize") in Sitecore Personalize.

When you send events, the Engage SDK automatically includes the browser ID in the event data object.

When you run experiences and experiments without including any optional guest identifier attributes in the personalization data object, the Engage SDK automatically includes the browser ID in the personalization data object.

## The browser ID in integrations using direct HTTP requests

You have to manually [request a browser ID](https://doc.sitecore.com/personalize/en/developers/api/stream-api/direct-http-requests-reference/retrieve-the-browser-id.html "Retrieve the browser ID") first. To do this, you make a GET request to the Browser API (Stream API type). The response includes the browser ID. In every event that you send to Sitecore Personalize, you have to manually include the browser ID.

## The browser ID in Sitecore Personalize

If you know the browser ID for a user of your app, you can use the browser ID to find data about the user in Sitecore Personalize.

If you have Sitecore Personalize but not Sitecore CDP, you can find the data in **Developer center** > **Event viewer**. In the search dropdown, select **Browser ID** and enter the browser ID in the search field. For example: a38b230c-11eb-4cf9-8d5d-274e9f344925​

If you have both Sitecore CDP and Sitecore Personalize, you can find the data in **Guests**. In the search dropdown, select **Browser ID** and enter the browser ID in the search field. For example: a38b230c-11eb-4cf9-8d5d-274e9f344925​