# MIME base64 encoding Characters (2.3.1 - 1.0.0) - HL7 v2.3.1 Vocabulary v0.1.0

* [**Table of Contents**](toc.md)
* [**Artifacts Summary**](artifacts.md)
* **MIME base64 encoding Characters (2.3.1 - 1.0.0)**

## CodeSystem: MIME base64 encoding Characters (2.3.1 - 1.0.0) (Experimental) 

| | |
| :--- | :--- |
| *Official URL*:http://terminology.hl7.org/v2plusvocab/CodeSystem/mimeBase64EncodingCharacters | *Version*:1.0.0 |
| Active as of 2026-01-27 | *Computable Name*:MimeBase64EncodingCharacters |
| *Other Identifiers:*OID:2.16.840.1.113883.18.180 | |
| **Copyright/Legal**: HL7 Inc., 2026 | |

 
HL7-defined code system of concepts specifying the characters used in the MIME Base 64 encoding mechanism. These are for reference only, as they are not carried as explicit code values in any HL7 coded field. This table was published only in releases 2.3, 2.3.1, and 2.4 of the Standard, and was removed thereafter. 

 This Code system is referenced in the content logical definition of the following value sets: 

* [Hl7VSmimeBase64EncodingCharacters](ValueSet-hl7VSmimeBase64EncodingCharacters.md)



## Resource Content

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```
