> ## Documentation Index
> Fetch the complete documentation index at: https://developers.pleo.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Authenticating Using API Keys

<Warning>
  **This page has now been ARCHIVED. Please visit:**

  * [Standalone API Keys Overview](/docs/current/authentication/standalone-api-keys-overview)
  * [Standalone API Key Workflow Guide](/docs/current/guides/standalone-api-keys-workflow-guide)
  * [How to Make an API Call Using a Standalone API Key](/docs/current/how-tos/api-keys/how-to-make-an-api-call-using-standalone-api-keys)
  * [How to Make an API Call Using a Standalone API Key (Postman)](/docs/current/how-tos/api-keys/how-to-make-an-api-call-using-standalone-api-keys-postman)
</Warning>

## Using API Keys in Curl

Specify the API key in the `-u` or `--user` flag. The password is an empty string.

Here is an example:

```bash theme={null}
curl --request GET -sL \\
     --url '<https://external.pleo.io/v1/installations/me>'\\
     -u 'enter the API key here'
```

## Using API Keys in a Graphical User Inteface (GUI) Tool

Here, we are using **Postman** for reference:

1. In the `Authorization` header of the request, select **Basic Auth** as the **Auth Type**.
2. In the `Username`, enter the API key.
3. In the `Password`, do not enter any value.

<Frame>
  <img src="https://mintcdn.com/pleo-61d4d38b/UuiilCOMmC9ytc__/images/docs/Authentication-using-API-keys/using-API-keys-in-GUI.png?fit=max&auto=format&n=UuiilCOMmC9ytc__&q=85&s=2510509be5f322a73e86f54f958a6ce9" alt="using API keys in GUI" width="2084" height="816" data-path="images/docs/Authentication-using-API-keys/using-API-keys-in-GUI.png" />
</Frame>