Format · HLS → MP4
Live replays: from HLS (m3u8) to a single MP4
Live broadcasts on X aren't single files. They're HLS streams: an .m3u8 playlist pointing at hundreds of short video segments. To give you one MP4, our server fetches the segments in order and remuxes them.
Updated
Download only content you own or have permission to use. Public posts only; we store no videos. Responsible use
HLS (m3u8) live replays technical sheet
- Source
- HLS master playlist (.m3u8) with one or more variants
- Variant used
- The first (top) variant listed in X's master playlist
- Processing
- Remux of MPEG-TS segments into fragmented MP4 (mux.js); no re-encoding
- Timestamps
- Normalized to start at 0 so desktop players open the file
- Output
account_postID_quality.mp4, streamed as it's built
Get HLS (m3u8) live replays from an X post
- Wait for the broadcast to end. Replays only appear after the host stops.
- Paste the broadcast or post link. Both
x.com/i/broadcasts/…links and posts that share a broadcast work. - Click a replay quality. The MP4 builds as it downloads; don't close the tab.
How HLS (m3u8) live replays works on X
When you click a replay quality, we fetch the master playlist, pick its variant, read the list of segments and download them one after another. Each segment's H.264 video and AAC audio are rewrapped into MP4 fragments and streamed to your browser right away, so the download starts before the whole replay is processed.
Remuxing changes the wrapper, not the picture: no quality is lost. Timestamps are reset to begin at zero, because a live stream's internal clock can start hours from zero and that makes some desktop players refuse the file.
While the broadcast is still running, the playlist keeps growing, so we show a player and no download until it ends (live still in progress).
HLS (m3u8) live replays by the numbers
| Replay length | What to expect |
|---|---|
| Under 15 min | Downloads quickly; MP3 also possible |
| 15–60 min | MP4 works; MP3 refused in the browser |
| Over an hour | Takes a while: every segment is fetched in sequence; keep the tab open |
Limits and honest caveats
- Fragmented MP4 plays in all modern players and editors; a few very old tools expect a classic MP4 — remux it once with
ffmpeg -i in.mp4 -c copy out.mp4. - If the host deleted the replay, there is nothing to fetch.
- Very long replays can fail if a segment can't be fetched in time; try again or pick a lower quality.
Why the file starts at 0:00 and plays everywhere
A live broadcast's segments carry timestamps from the stream's own clock, which can begin hours after zero. Saved as-is, some desktop players would show a blank screen or a strange duration. We shift every segment so the first frame sits at zero, which is why the replay opens and seeks normally in QuickTime, VLC and editors.
Remuxing keeps the bitrate of the variant X lists first, so a long 1080p replay can be several hundred megabytes. If you only need part of it, trim it afterwards with any editor that supports stream copy, which cuts without re-encoding.
Questions people ask
Can I paste an .m3u8 URL directly?
No, paste the X post or broadcast link; we find the playlist ourselves.
Is the replay re-encoded?
No, it's remuxed: same video and audio, new container.
Why is the MP4 download slow for long lives?
Every segment is fetched from X in sequence and assembled as it goes.