# Authentication

## Authentication Methods

There are two primary ways to obtain an access token:

1. [Password-Based Authentication](/services/parchment-digital-badges/authentication/password-based-authentication.md): Use your username and password to obtain an access token.
2. [Authorization Code-Based Authentication](/services/parchment-digital-badges/authentication/authorization-code-based-authentication.md): Use OAuth2 to obtain an access token via an authorization code grant.

## Authenticating Requests

Once you obtained an access token from the Parchment Digital Badges API domain for your region, you'll need to provide an Authorization header of type "Bearer" for all additional requests. For example:

```bash
curl 'https://{BADGES_DOMAIN}/v2/users/self' -H "Authorization: Bearer YOURACCESSTOKEN"
```

## Token Expiration

Access tokens will expire, and if an expired token is used, a 401 status code will be returned.

The refresh token can be used to automatically renew an access token without requiring the password again. For example:

```bash
curl -X POST 'https://{BADGES_DOMAIN}/o/token' -d "grant_type=refresh_token&refresh_token=YOURREFRESHTOKEN"
```


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