RFC 1521 · DRAFT STANDARD · 1993

MIME Part One: Mechanisms for Specifying and Describing the Format of Internet Message Bodies

Overview

RFC 1521, “MIME Part One: Mechanisms for Specifying and Describing the Format of Internet Message Bodies”, is a Draft Standard document published in September 1993 by N. Borenstein, N. Freed. It obsoletes RFC 1341. It has since been updated by RFC 1590. It has been obsoleted by RFC 2045, RFC 2046, RFC 2047, RFC 2048, RFC 2049 — refer to the newer document for the authoritative version. The canonical text is published by the RFC Editor.

Abstract

This document redefines the format of message bodies to allow multi-part textual and non-textual message bodies to be represented and exchanged without loss of information. This is based on earlier work documented in RFC 934 and STD 11, RFC 1049, but extends and revises that work. [STANDARDS-TRACK]

Abstract as published in the RFC, via rfc-editor.org.

What “Draft Standard” means

A historical maturity level (retired in 2011) that sat between Proposed Standard and Internet Standard and required multiple interoperable implementations.

Read this RFC

The canonical text of RFC 1521 is hosted at rfc-editor.org. Available in TXT,PS,PDF,HTML.

Relationships to other RFCs
This RFC obsoletes
RFC 1341
Updated by
RFC 1590
Other RFCs from 1993

Who Is Online

In total there are 65 users online: 0 registered, 57 guests and 8 bots.

Most users ever online was 5,555 on 17 Jul 2026, 3:23 am.

Bots: AhrefsBot Applebot Baiduspider Bingbot Googlebot Other Bot PetalBot SemrushBot

Users active in the past 15 minutes. Total registered members: 372