# Customer.io credentials

You can use these credentials to authenticate the following nodes with Customer.io.

- [Customer.io](/guides/automated-workflows/integrations/builtin/app-nodes/ts-wf-nodes-base.customerio)
- [Customer.io Trigger](#)


## Prerequisites

Create a [Customer.io](https://customer.io/) account.

## Supported authentication methods

- API Key


## Related resources

For detailed API reference documentation for each API, refer to the [Track API documentation](https://customer.io/docs/api/track/) and the [App API documentation](https://customer.io/docs/api/app/).

## Using API key

To configure this credential, you'll need:

- A **Tracking API Key**: For use with the [Track API](https://customer.io/docs/api/track/) at `https://track.customer.io/api/v1/`. See the FAQs below for more details.
- Your **Region**: Customer.io uses different API subdomains depending on the region you select. Options include:
  - **Global region**: Keeps the default URLs for both APIs; for use in all non-EU countries/regions.
  - **EU region**: Adjusts the Track API subdomain to `track-eu` and the App API subdomain to `api-eu`; only use this if you are in the EU.
- A **Tracking Site ID**: Required with your **Tracking API Key**
- An **App API Key**: For use with the [App API](https://customer.io/docs/api/app/) at `https://api.customer.io/v1/api/`. See the FAQs below for more details.


Refer to the [Customer.io Finding and managing your API credentials documentation](https://customer.io/docs/accounts-and-workspaces/managing-credentials/) for instructions on creating both Tracking API and App API keys.

## Why you need a Tracking API Key and an App API Key

Customer.io has two different API endpoints and generates and stores the keys for each slightly differently:

- The [Track API](https://customer.io/docs/api/track/) at `https://track.customer.io/api/v1/`
- The [App API](https://customer.io/docs/api/app/) at `https://api.customer.io/v1/api/`


The Track API requires a Tracking Site ID; the App API doesn't.

Based on the operation you want to perform, Mosaic Workflows uses the correct API key and its corresponding endpoint.