# Tag


A label consisting of a user-defined key and value. The form for tags is \$1"Key", "Value"\$1

## Contents


 ** Key **   <a name="HealthLake-Type-Tag-Key"></a>
The key portion of a tag. Tag keys are case sensitive.   
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 128.  
Pattern: `^([\p{L}\p{Z}\p{N}_.:/=+\-@]*)$`   
Required: Yes

 ** Value **   <a name="HealthLake-Type-Tag-Value"></a>
 The value portion of a tag. Tag values are case-sensitive.  
Type: String  
Length Constraints: Minimum length of 0. Maximum length of 256.  
Pattern: `^([\p{L}\p{Z}\p{N}_.:/=+\-@]*)$`   
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/healthlake-2017-07-01/Tag) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/healthlake-2017-07-01/Tag) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/healthlake-2017-07-01/Tag)