# Tag
<a name="API_domains_Tag"></a>

Each tag includes the following elements.

## Contents
<a name="API_domains_Tag_Contents"></a>

 ** Key **   <a name="Route53Domains-Type-domains_Tag-Key"></a>
The key (name) of a tag.  
Valid values: A-Z, a-z, 0-9, space, ".:/=\$1\$1-@"  
Constraints: Each key can be 1-128 characters long.  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 128.  
Required: No

 ** Value **   <a name="Route53Domains-Type-domains_Tag-Value"></a>
The value of a tag.  
Valid values: A-Z, a-z, 0-9, space, ".:/=\$1\$1-@"  
Constraints: Each value can be 0-256 characters long.  
Type: String  
Length Constraints: Minimum length of 0. Maximum length of 256.  
Required: No

## See Also
<a name="API_domains_Tag_SeeAlso"></a>

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/route53domains-2014-05-15/Tag) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/route53domains-2014-05-15/Tag) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/route53domains-2014-05-15/Tag)