M3U File: What It Is and How to Open One

What is an M3U file?

An M3U file is a text file that lists media files or stream addresses, one per line. It has no formal specification and is a de facto standard. Extended files begin with #EXTM3U and add #EXTINF lines that give a title and duration for the entry below. An M3U8 file uses the same layout, saved as UTF-8 text.

How to open an M3U or M3U8 file

1. Open the file in a media player that supports playlists, such as VLC.
2. If it opens as text instead, check the first line. An extended file should start with #EXTM3U.
3. To see every line before loading it, use the M3U file inspector.

If the file still will not open, read the not-opening guide.

How the inspector works

Choose a file or paste its text. The inspector reads it in your browser and reports the header, the number of lines, the entries it finds, each entry's #EXTINF details and attributes, and any lines that do not match the expected layout. Every issue is listed with its line number. The report describes the text only; it does not open the addresses in the file or check whether they respond.

Use it when you want to see what is actually in a file before you load it into a player or an editor, or when you need to find the line causing a problem.

What the guides cover

The first guide explains what the format is and what a playlist file does not contain. The anatomy guide walks through a short example one line at a time. The not-opening guide lists the usual reasons a player or editor rejects a file. The guides cover the file itself, not how to build or publish a playlist.

M3U and M3U8 files

An M3U file and an M3U8 file use the same line-based text layout. M3U8 files are saved as UTF-8 text, which lets them hold characters outside the basic Latin set. Most players read both. The name M3U is generally described as an abbreviation of "MP3 URL", although sources differ on where the format first appeared, so treat any single origin story with care.

A typical file starts with #EXTM3U, then pairs each channel or track's #EXTINF line with the address or path on the line below it. Lines beginning with # that are not recognised tags are treated as comments by most players.

Frequently asked questions

Is an M3U file the same as an M3U8 file?

The layout is the same. The difference is encoding: M3U8 is saved as UTF-8. Many tools read both extensions.

How do I open a .m3u8 file?

A .m3u8 file is a text playlist, so any plain-text editor will show it. A media player that supports M3U8 opens it as a playlist. To read every line before you load it, use the M3U file inspector.

What does a .m3u file contain?

A .m3u file lists media locations, one per line, and may include #EXTINF lines that give a title for each entry. It holds the locations only, not the audio or video data itself.

Can the inspector open a playlist that is online?

It reads the file's text only. It does not open or test the addresses inside the file.

Does the inspector upload my file?

No. The file is read in your browser tab and is not sent to a server.

What this site does not do

The inspector reads text; it does not play streams, test whether an address is live, or judge whether any stream is legal to watch. It does not host, copy or relay the contents of any file. Your file is read in the browser tab and is not uploaded.