What is the difference between a master and a media playlist?

A master playlist (with EXT-X-STREAM-INF tags) lists the available quality variants and points to a media playlist for each. A media playlist lists the actual .ts or fMP4 segments with their durations. The parser detects which kind you provided.

How are segment durations read?

Each segment is preceded by an #EXTINF: , tag. The parser reads that floating-point duration and sums them to report the total playlist length, matching how players compute it.

Does it show encryption information?

Yes. #EXT-X-KEY tags are parsed for their METHOD (such as AES-128 or SAMPLE-AES) and key URI, so you can see whether and how segments are encrypted.

How can I tell live from VOD?

A media playlist ending with #EXT-X-ENDLIST is video-on-demand (the full segment list is known). Without ENDLIST it is a live playlist that the player would keep refreshing. The parser labels each case.

Is anything uploaded?

No. The file is read as text in your browser and parsed with plain string logic. Nothing is sent to a server, so it works offline and your playlist stays private.

M3U8 / HLS Playlist Parser

Inspect any HLS playlist without a player

An M3U8 parser breaks down an HLS playlist so you can see exactly what a video player would: the quality variants, the segment list, encryption, and timing tags. It is useful for debugging streaming setups, verifying an encoder’s output, or auditing a stream’s structure — all locally.

How it works

The parser follows the HLS specification (RFC 8216). It first confirms the #EXTM3U header, then decides the playlist type: if any #EXT-X-STREAM-INF tag is present it is a master playlist, otherwise a media playlist.

For master playlists it reads each #EXT-X-STREAM-INF attribute list — BANDWIDTH, RESOLUTION, CODECS, FRAME-RATE — pairing it with the URI on the following line, and also lists #EXT-X-MEDIA alternate audio and subtitle renditions. For media playlists it walks the tags in order, attaching each #EXTINF duration, #EXT-X-BYTERANGE, and #EXT-X-DISCONTINUITY to the segment URI that follows, and reads #EXT-X-VERSION, #EXT-X-TARGETDURATION, #EXT-X-KEY, and #EXT-X-ENDLIST. Attribute lists are split with a quote-aware regex so commas inside quoted CODECS values are not mistaken for separators.

Tips and notes

Variant streams are sorted by bandwidth (highest first) so the top entry is the best-quality rendition.
A missing #EXT-X-ENDLIST means the playlist is live; players would re-fetch it on the target-duration interval.
The #EXT-X-KEY method tells you the encryption scheme — NONE, AES-128, or SAMPLE-AES. The key URI is where the player fetches the decryption key.
The parser works on local text only, so it cannot follow relative segment URIs to a server; it reports them exactly as written.