Extract subtitles from a video (MKV, MP4)
An MKV movie often contains several subtitle tracks (French, English, commentary…). ffmpeg extracts them as standalone text files (SRT, ASS or WebVTT) that you can edit, translate or use with another player.
Updated on
0 is the first subtitle track in the file, 1 the second… To list them, use the file information page.
How to use it
- Install ffmpeg if you haven't already.
- Open a terminal in the folder containing the video.
- Copy the generated command, adjust the file names if needed, then run it.
- Open the resulting file to check the result.
Using the extracted file
Put the SRT file next to the video with the same name (movie.mkv and movie.srt): most players, such as VLC, display it automatically. To burn it into a video, use the dedicated page.
Multiple languages
If the file contains subtitles in several languages, run the command for each track number. The output file name includes the track number to avoid overwriting.
Frequently asked questions
How do I know which tracks the file contains?
The file information page shows the list of tracks with their language. In the ffprobe output, look for the "Subtitle" lines: the first one is track 0.
Why does extraction fail for DVD or Blu-ray subtitles?
Those subtitles are images (PGS, VobSub formats), not text: ffmpeg can't convert them to SRT. You need optical character recognition (OCR) software such as Subtitle Edit.
What's the difference between SRT and ASS?
SRT only contains the text and the timing. ASS also keeps fonts, colors and positions: it's the subtitle format used for anime. Converting ASS to SRT loses that formatting.
Can I extract without converting?
Yes, with "-c:s copy" and the extension matching the original format (for example .ass if the track is ASS). You then need to know the track's format.