# Authenticate user without credentials

**URL:** <https://forum.keycloak.org/t/authenticate-user-without-credentials/25533>\
**Category:** Getting advice\
**Tags:** authentication\
**Created:** [April 12, 2024, 8:09am UTC](https://forum.keycloak.org/t/authenticate-user-without-credentials/25533 "2024-04-12T08:09:32Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![bikalpa-thapa](https://yyz2.discourse-cdn.com/free1/user_avatar/forum.keycloak.org/bikalpa-thapa/32/10208_2.png) [@bikalpa-thapa](https://forum.keycloak.org/u/bikalpa-thapa)\
**Post date:** [April 12, 2024, 8:09am UTC](https://forum.keycloak.org/t/authenticate-user-without-credentials/25533/1 "2024-04-12T08:09:32Z")

</div>

Is there a way to authenticate user automatically based on IP of the user. The user will be only one but he/she can login to multiple devices directly without the login screen if the said user is from certain ip

---

<div class="post-metadata">

**Author:** ![xgp](https://yyz2.discourse-cdn.com/free1/user_avatar/forum.keycloak.org/xgp/32/2589_2.png) [@xgp](https://forum.keycloak.org/u/xgp)\
**Post date:** [April 12, 2024, 9:54am UTC](https://forum.keycloak.org/t/authenticate-user-without-credentials/25533/2 "2024-04-12T09:54:18Z")

</div>

You would need to implement a custom Authenticator in order to do that. See the Server Developer Guide section on Authentication for more information:  
[https://www.keycloak.org/docs/latest/server\_development/index.html#\_auth\_spi](https://www.keycloak.org/docs/latest/server_development/index.html#_auth_spi)