# Tag


The Tag type enables you to specify a key-value pair that can be used to store information about an CloudFormation stack.

## Contents


 ** Key **   
A string used to identify this tag. You can specify a maximum of 128 characters for a tag key. Tags owned by AWS have the reserved prefix: `aws:`.  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 128.  
Required: Yes

 ** Value **   
A string that contains the value for this tag. You can specify a maximum of 256 characters for a tag value.  
Type: String  
Length Constraints: Minimum length of 1. 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/cloudformation-2010-05-15/Tag) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/cloudformation-2010-05-15/Tag) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/cloudformation-2010-05-15/Tag)