¿Qué es M3U8?
Guía práctica del formato de playlist M3U8 y el protocolo HLS streaming.
Introducción
M3U8 es un formato de playlist UTF-8 usado por HLS (HTTP Live Streaming). Normalmente no contiene el video, sino segmentos, variantes, claves y metadatos.
HLS fue introducido por Apple y hoy se usa ampliamente para live streaming y VOD en navegadores, apps y plataformas OTT.
Cómo funciona M3U8
1. Server segmentation
The server splits a video into short TS or fMP4 segments and writes an M3U8 index file.
2. M3U8 index
The playlist records segment URLs, playback order, duration, variants, and related metadata.
3. Progressive download
The player downloads segments in order and starts playback before the full video is available.
4. Adaptive bitrate
A master playlist can provide multiple qualities, so the player switches according to network conditions.
Estructura del archivo M3U8
#EXTM3U
#EXT-X-VERSION:3
#EXT-X-TARGETDURATION:10
#EXT-X-MEDIA-SEQUENCE:0
#EXTINF:9.009,
http://media.example.com/first.ts
#EXTINF:9.009,
http://media.example.com/second.ts
#EXTINF:3.003,
http://media.example.com/third.ts
#EXT-X-ENDLIST#EXTM3U - file header for an M3U playlist
#EXT-X-VERSION - HLS protocol version
#EXT-X-TARGETDURATION - maximum segment duration
#EXTINF - segment duration and URL
#EXT-X-ENDLIST - marks VOD playlist end
M3U8 vs MP4
Ventajas de M3U8
- Supports live streaming.
- Adapts quality to bandwidth.
- Starts quickly without downloading the full file.
- Works well with CDN caching.
- Supports encryption.
Limitaciones de M3U8
- Not ideal for local file playback without an HTTP server.
- Many files can be harder to manage.
- Latency can be higher than direct file playback.
- Older devices may need a compatible player.
- Saving offline is less simple than MP4.
Casos de uso comunes
Live video
Sports, news, events, and game streams.
VOD platforms
Video sites, online education, and OTT libraries.
Mobile apps
Video playback in phone and tablet applications.
Cómo usar M3U8
Online playback
Open a direct M3U8 URL in an HLS-capable player such as M3U8 Player.
Download and save
Use an M3U8 downloader to fetch segments and merge them when you have permission.
Format conversion
Use FFmpeg or a converter to create MP4 from an allowed M3U8 source.