Infobox file format
name = M3U
extension = .m3u
mime = audio/x-mpegurl
owner = Nullsoft
creatorcode = M3U
genre = Playlist
containerfor =
containedby =
extendedfrom =
extendedto =

M3U (Moving Picture Experts Group Audio Layer 3 Uniform Resource Locator, MP3 URL) is a computer file format that stores multimedia playlists. It was originally implemented in Winamp, although it is now supported by many applications.

An M3U file is a plain text file that contains the locations of one or more media files that the mediaplayer should play. Each location is placed on a new line. The locations can be either absolute or relative local pathnames (e.g., "C:My MusicChanson.mp3" or "Chanson.mp3") or they can be URLs. The file can also include comments, prefaced by the "#" character. In extended M3U, "#" also introduces extended M3U directives.

One common use of the M3U file format is creating a playlist file that contains a single entry pointing to a stream on the Internet. The created file provides easy access to that stream and can be used for things like downloading from a website or for emailing, or for Internet radio listening.

The file is saved with the "M3U" or "m3u" filename extension.

"m3u" files properly use the Latin-1 charset, the unicode version of "m3u" is "m3u8", it can include UTF-8 unicode characters. Many applications can treat a m3u file as UTF-8, however.

Compare with

* Advanced Stream Redirector (ASX)
* PLS (file format)
* B4S (file format) Winamp3 XML based playlist format
* WPL Windows Media Player Playlist


Here is an example of an extended M3U file on the Windows platform. Sample.mp3 and Example.ogg are the media files. 123 and 321 are the lengths by seconds. A length of -1 may be used when the media file is a streaming file, as there is no predefined actual length value possible. The value after the length is the title to be shown, which is generally the same as the location of the file which is on the second line. On the Mac OS X and Linux platforms, Unix paths are used. #EXTM3U #EXTINF:123,Sample title C:Documents and SettingsIMy MusicSample.mp3 #EXTINF:321,Example title C:Documents and SettingsIMy MusicGreatest HitsExample.oggThis example shows how to create an m3u file linking to a specified folder (Flash drive, CD-ROM, for example). The m3u file should contain only one string: the path to the folder. After starting up, the media player will play all contents of the folder: C:Music

Here is another example, in relative format. The M3U file is placed in the same folder as the music, and directories must be preserved when moving the playlist to another device if subfolders are used. This method is more compatible as it doesn't rely on the file path staying the same.
This is the same file as above, saved as sample.m3u in C:Documents and SettingsIMy Music #EXTM3U #EXTINF:123,Sample title Sample.mp3 #EXTINF:321,Example title Greatest HitsExample.oggThis format in an M3U allows you to copy it to another device for playback, if you copy all files and folders it refers to.

External links

* [http://forums.winamp.com/showthread.php?threadid=65772 Definition of basic M3U format.] Also includes PLS.
* [http://hanna.pyxidis.org/tech/m3u.html Definition of the extended M3U format.] Includes guide to hand-coding m3u files.
* [http://gonze.com/playlists/playlist-format-survey.html A survey of playlist formats]

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