# Login German username with Case-insensitive

**URL:** <https://forum.keycloak.org/t/login-german-username-with-case-insensitive/12278>\
**Category:** Securing applications\
**Tags:** admin-console, authentication, database, identity-brokering, saml\
**Created:** [November 24, 2021, 6:22am UTC](https://forum.keycloak.org/t/login-german-username-with-case-insensitive/12278 "2021-11-24T06:22:17Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![rajyadav](https://avatars.discourse-cdn.com/v4/letter/r/65b543/32.png) [@rajyadav](https://forum.keycloak.org/u/rajyadav)\
**Post date:** [November 24, 2021, 6:22am UTC](https://forum.keycloak.org/t/login-german-username-with-case-insensitive/12278/1 "2021-11-24T06:22:18Z")

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Example from German username:  
Uppercase (Goethestraße) = GOETHESTRASZE or GOETHESTRASSE  
Use case:  
How keycloak would differentiate between these users and how does it prevent one user getting access to other user account in such cases?

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**Author:** ![rajyadav](https://avatars.discourse-cdn.com/v4/letter/r/65b543/32.png) [@rajyadav](https://forum.keycloak.org/u/rajyadav)\
**Post date:** [November 24, 2021, 8:14am UTC](https://forum.keycloak.org/t/login-german-username-with-case-insensitive/12278/2 "2021-11-24T08:14:54Z")

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@xgp @dasniko @mbonn@bpedersen2 Please look into this

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**Author:** ![dasniko](https://yyz2.discourse-cdn.com/free1/user_avatar/forum.keycloak.org/dasniko/32/2969_2.png) [@dasniko](https://forum.keycloak.org/u/dasniko)\
**Post date:** [November 24, 2021, 8:59am UTC](https://forum.keycloak.org/t/login-german-username-with-case-insensitive/12278/3 "2021-11-24T08:59:06Z")

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No need to stress people here by mentions. Especially not after that short amount of time. Think of different timezones and different lifestyles, maybe someone else is still sleeping when you are awake.  
I’m pretty sure, all of the mentioned people will read your post and if they are able to help / know an answer, they will post it here.

Back to your issue:  
Keycloak handles all usernames lowercase and has no clue of special language spellings. So, `SZ` will transform with a `.toLowerCase()` method into `sz`, and `SS` into `ss`. There’s no hint that a `ß` should be used, as this is only a german written rule, but has no counterpart in any encoding.  
Thus, `GOETHESTRASZE` and `GOETHESTRASSE` are two different usernames for Keycloak.

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**Author:** ![rajyadav](https://avatars.discourse-cdn.com/v4/letter/r/65b543/32.png) [@rajyadav](https://forum.keycloak.org/u/rajyadav)\
**Post date:** [November 24, 2021, 9:47am UTC](https://forum.keycloak.org/t/login-german-username-with-case-insensitive/12278/4 "2021-11-24T09:47:52Z")

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Sorry for Tag , Thanks for your quick reply

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**Author:** ![rajyadav](https://avatars.discourse-cdn.com/v4/letter/r/65b543/32.png) [@rajyadav](https://forum.keycloak.org/u/rajyadav)\
**Post date:** [November 24, 2021, 12:25pm UTC](https://forum.keycloak.org/t/login-german-username-with-case-insensitive/12278/5 "2021-11-24T12:25:21Z")

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is keycloak support localization ?

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**Author:** ![dasniko](https://yyz2.discourse-cdn.com/free1/user_avatar/forum.keycloak.org/dasniko/32/2969_2.png) [@dasniko](https://forum.keycloak.org/u/dasniko)\
**Post date:** [November 24, 2021, 12:57pm UTC](https://forum.keycloak.org/t/login-german-username-with-case-insensitive/12278/6 "2021-11-24T12:57:26Z")

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yes, of course. but this doesn’t solve the problem.  
localization is for displaying labels, messages, etc. in proper language.  
there’s no impact on how data is handled.