---
type: api
title: Authentication
url: https://www.elastic.co/elastic/docs-builder/docs/4371/api/doc/cloud-serverless/authentication
resource: https://www.elastic.co/elastic/docs-builder/docs/4371/api/doc/cloud-serverless/authentication
products:
  - Elastic Cloud Serverless
---

# Authentication

## Api key (apiKey)

API keys are used to authenticate requests to the Elastic Cloud Serverless REST API.
Generate your secret API key in https://cloud.elastic.co/account/keys
You must provide the API key for all API requests in the Authorization header as follows:

```
"Authorization: ApiKey $API_KEY"
```

For example, if you interact with the API using the curl command:

```
curl -H "Authorization: ApiKey essu_..." https://api.elastic-cloud.com/api/v1/serverless/projects/elasticsearch
```

```http
Authorization: <value>
```