How to get access token from Keycloak using Postman — OAuth2

Here’s how to setup Postman to authenticate on Keycloak using a public client and the Authorization Code grant type.

The configuration of the public client should look like this. We will add another valid redirect URI later on.

Realm id is myRealm

Client id is myPublicClientId

My Keycloak instance is deployed locally at this address http://localhost:9080/auth

In Postman, in the Authorization tab, select OAuth 2.0 and in the configure options:

Auth URL: http://localhost:9080/auth/realms/myRealm/protocol/openid-connect/auth

Access Token URL: http://localhost:9080/auth/realms/myRealm/protocol/openid-connect/token

Click on “Get New Access Token”, it will open the browser. You should see when trying to authenticate.

This is because we need to add another valid URI in public client configuration:

This is the callback url defined in Postman. Add it and save. Once it is done, request for a new Access Token and voila!