# API Clients

View, create, and delete API Clients

To interact with the commercetools commerce APIs, use an API Client with dedicated [scopes](https://docs.commercetools.com/api/scopes.md) that allow read or write access to resources within your project.

You must create your first API Client in the [Merchant Center](https://docs.commercetools.com/merchant-center/developer-settings.md#api-clients). After that, you can create additional API Clients in the Merchant Center or through this API. You can use the API Clients endpoints only from an [authorized API Client](https://docs.commercetools.com/api/authorization.md#authorization-overview).

The API Clients API is especially useful for Infrastructure as Code (IaC) tooling and for frequently rotating your API secrets.

The APIs use OAuth 2.0 for [authorization](https://docs.commercetools.com/api/authorization.md).

Once you create an API Client, you cannot change it. The `secret` is visible only in the response when creating the API Client.

This API allows you to configure the expiration times of OAuth tokens for your API Client. If you want to set expiration times different to the default values shown below, you need to use this API instead of the Merchant Center for creating your API Client.

(a CSV formatted table follows. The first line are the column names.)
Token type,Default,Minimum,Maximum
access token,48 hours,1 hour,7 days
refresh token,200 days,30 seconds,1 year


Due to the sensitive nature of this API, it can not be used with the `manage_project:{projectKey}` scope, but only with `manage_api_clients:{projectKey}`.

Learn more about OAuth 2.0 for API authentication in our self-paced Authorization flows and API Clients module.

## Representations

#### APIClient

See API type definition [ApiClient](https://docs.commercetools.com/api/projects/api-clients.md?urn=ctp%3Aapi%3Atype%3AApiClient).

#### APIClientDraft

See API type definition [ApiClientDraft](https://docs.commercetools.com/api/projects/api-clients.md?urn=ctp%3Aapi%3Atype%3AApiClientDraft).

#### ApiClientPagedQueryResponse

See API type definition [ApiClientPagedQueryResponse](https://docs.commercetools.com/api/projects/api-clients.md?urn=ctp%3Aapi%3Atype%3AApiClientPagedQueryResponse).

## Get API Client

See API endpoint definition [GET /\{projectKey}/api-clients/\{id}](https://docs.commercetools.com/api/projects/api-clients.md?urn=ctp%3Aapi%3Aendpoint%3A%2F%7BprojectKey%7D%2Fapi-clients%2F%7Bid%7D%3AGET).

## Query API Clients

See API endpoint definition [GET /\{projectKey}/api-clients](https://docs.commercetools.com/api/projects/api-clients.md?urn=ctp%3Aapi%3Aendpoint%3A%2F%7BprojectKey%7D%2Fapi-clients%3AGET).

## Check if API Client exists

### Check if API Client exists by ID

See API endpoint definition [HEAD /\{projectKey}/api-clients/\{id}](https://docs.commercetools.com/api/projects/api-clients.md?urn=ctp%3Aapi%3Aendpoint%3A%2F%7BprojectKey%7D%2Fapi-clients%2F%7Bid%7D%3AHEAD).

### Check if API Client exists by Query Predicate

See API endpoint definition [HEAD /\{projectKey}/api-clients](https://docs.commercetools.com/api/projects/api-clients.md?urn=ctp%3Aapi%3Aendpoint%3A%2F%7BprojectKey%7D%2Fapi-clients%3AHEAD).

## Create API Client

Scopes cannot be changed after an API Client is created.

See API endpoint definition [POST /\{projectKey}/api-clients](https://docs.commercetools.com/api/projects/api-clients.md?urn=ctp%3Aapi%3Aendpoint%3A%2F%7BprojectKey%7D%2Fapi-clients%3APOST).

## Delete API Client

See API endpoint definition [DELETE /\{projectKey}/api-clients/\{id}](https://docs.commercetools.com/api/projects/api-clients.md?urn=ctp%3Aapi%3Aendpoint%3A%2F%7BprojectKey%7D%2Fapi-clients%2F%7Bid%7D%3ADELETE).

## Related pages

- [Section overview page](https://docs.commercetools.com/api.md)
- [Previous page: Scopes](https://docs.commercetools.com/api/scopes.md)
- [Next page: GDPR compliance](https://docs.commercetools.com/api/gdpr.md)