# Tag


A key-value pair. A tag consists of a tag key and a tag value. Tag keys and tag values are both required, but tag values can be empty (null) strings.

**Important**  
Do not include confidential or sensitive information in this field. 

For more information, see [User-Defined Tag Restrictions](https://docs.aws.amazon.com/awsaccountbilling/latest/aboutv2/allocation-tag-restrictions.html) in the *AWS Billing and Cost Management User Guide*.

## Contents


 ** TagKey **   <a name="qdevinchatapps-Type-Tag-TagKey"></a>
The key of the tag.  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 128.  
Required: Yes

 ** TagValue **   <a name="qdevinchatapps-Type-Tag-TagValue"></a>
The value of the tag.  
Type: String  
Length Constraints: Minimum length of 0. Maximum length of 256.  
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/chatbot-2017-10-11/Tag) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/chatbot-2017-10-11/Tag) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/chatbot-2017-10-11/Tag)