Site Logotype, floated left.
MT File Information Schemas:

ID3 Tags

CC-BY-SA
This work is licensed under the Creative Commons Attribution-ShareAlike License 4.0.

Latest Version: A
https://ns.sm0tvi.net/finfo/application/prs.id3/index.shtml

Introduction

When the MP3 standard was published in 1995, it did not include a method for storing file metadata.

ID3 is a metadata container most often used in conjunction with the MP3 audio file format. It allows information such as the title, artist, album, track number, and other information about the file to be stored in the file itself.

ID3 is a de facto standard for metadata in MP3 files; no standardization body was involved in its creation nor has such an organization given it a formal approval status. It competes with the APE Tag in this arena.

There are two unrelated versions of ID3: ID3v1 and ID3v2. In ID3v1, the metadata is stored in a 128-byte segment at the end of the file. In ID3v2, an extensible set of “frames” located at the start of the file. Subvariants of both versions exist.

Version 1

In 1996, Eric Kemp proposed adding a 128-byte suffix to MP3 files in which useful information such as an artist's name or a related album title could be stored. Kemp deliberately placed the tag data (which is demarcated with the 3-byte string “TAG”) at the end of the file as it would cause a short burst of static to be played by older media players that did not support the tag. The method, now known as ID3v1, quickly became the de facto standard for storing metadata in MP3s despite internationalization and localization weaknesses arising from the standard's use of ISO-8859-1 system of encoding rather than the more globally compatible Unicode.

The v1 tag allows 30 bytes each for the title, artist, album, and a “comment”, 4 bytes for the year, and 1 byte to identify the genre of the song from a predefined list of values.

Version 1.1

In 1997, a modification to ID3v1 was proposed by Michael Mutschler in which two bytes formerly allocated to the comment field were used instead to store a track number so that albums stored across multiple files could be correctly ordered. The modified format became known as ID3v1.1.

Version 1.2

In 2002 or 2003, BirdCage Software proposed ID3v1.2, which enlarged many of the fields from 30 to 60 bytes and added a subgenre field while retaining backward compatibility with v1.1 by placing its new “enhanced” tag in front of a standard v1.1 tag. Adoption of ID3v1.2 was limited.

Version 2

In 1998, a new specification called ID3v2 was created by multiple contributors. Although it bears the name ID3, its structure completely distinct from that of ID3v1. ID3v2 tags are of variable size and are usually placed at the start of the file, which enables metadata to load immediately, even when the file as a whole is loading incrementally during streaming.

A ID3v2 tag consists of a number of optional frames, each of which contains a piece of metadata up to 16 MB in size. For example, a TT2 frame may be included to contain a title. The entire tag may be as large as 256 MB, and strings may be encoded in Unicode.

Version 2.2.0

The first public variant of v2, ID3v2.2 replaced three-characters frame identifiers (e.g., TT2) with four-character frame identifiers (e.g., TIT2) in order to avoid confusion between similar codes. Most of the common v2.3 and v2.4 frames have direct analogues in v2.2, but v2.2 is now considered obsolete.

Version 2.3.0

ID3v2.3 is the most widely used version of ID3v2 tags and is widely supported by Windows Explorer and Windows Media Player. Notably it introduced the ability to embed an image such as an album cover.

Version 2.4.0

ID3v2.4 was published on November 1, 2000. It defines 83 frame types, allows text frames to contain multiple values separated with a null byte, and permits the tag to be stored at either the beginning or the end of the file.

Tag —

Frame —

Group —

GRID — Group Identification Registration

Glossary

Words and terms introduced in this document.

MP3 · MPEG-1 Audio Layer III · MPEG-2 Audio Layer III:
An open standard lossy compression format for digital audio developed largely by the Fraunhofer Society in Germany under the lead of Karlheinz Brandenburg, with support from other digital scientists in the United States and elsewhere.
See also the Wikipedia article on “MP3”

References and Further Reading