# UsernameConfigurationType


The configuration of a user pool for username case sensitivity.

This data type is a request and response parameter of [CreateUserPool](API_CreateUserPool.md) and [UpdateUserPool](API_UpdateUserPool.md), and a response parameter of [DescribeUserPool](API_DescribeUserPool.md).

## Contents


 ** CaseSensitive **   <a name="CognitoUserPools-Type-UsernameConfigurationType-CaseSensitive"></a>
Specifies whether user name case sensitivity will be applied for all users in the user pool through Amazon Cognito APIs. For most use cases, set case sensitivity to `False` (case insensitive) as a best practice. When usernames and email addresses are case insensitive, users can sign in as the same user when they enter a different capitalization of their user name.  
Valid values include:    
true  
Enables case sensitivity for all username input. When this option is set to `true`, users must sign in using the exact capitalization of their given username, such as “UserName”. This is the default value.  
false  
Enables case insensitivity for all username input. For example, when this option is set to `false`, users can sign in using `username`, `USERNAME`, or `UserName`. This option also enables both `preferred_username` and `email` alias to be case insensitive, in addition to the `username` attribute.
Type: Boolean  
Required: Yes

## See Also


For more information about using this API in one of the language-specific AWS SDKs, see the following:
+  [AWS SDK for C\$1\$1](https://docs.aws.amazon.com/goto/SdkForCpp/cognito-idp-2016-04-18/UsernameConfigurationType) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/cognito-idp-2016-04-18/UsernameConfigurationType) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/cognito-idp-2016-04-18/UsernameConfigurationType)