Convert Matroska (MKV) to MP3
Free online converter for Matroska (MKV) files. The most widely compatible lossy audio format. Nothing to install, no watermark, and every file is deleted automatically.
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Upload a Matroska (MKV) file to convert it to MP3. Up to 3 files at once, 100 MB each.
Free · up to 3 files · 100 MB each · files deleted automatically after 1 hour.
About MKV and MP3
Matroska (MKV) .mkv
Matroska: an open container that will hold almost any combination of video, audio, subtitle and chapter tracks in one file.
Good for
- Unlimited tracks — multiple languages, subtitles, chapters
- Codec-agnostic, so it holds nearly anything
- Open, well documented, and resilient to damage
Trade-offs
- Browsers will not play it natively
- Many TVs and phones refuse it — the usual reason to convert
- Being a container, contents vary wildly file to file
video/x-matroska
MP3 .mp3
The format that made digital music portable. Lossy, thirty years old, and still the safest choice when you have no idea what will play the file.
Good for
- Plays on essentially every device ever made
- Small files at listenable quality
- Patents long expired, so support is everywhere
Trade-offs
- Lossy — detail is gone permanently
- Beaten by AAC and Opus at the same bitrate
- No transparency about what was discarded
audio/mpeg
MKV and MP3 side by side
| MKV | MP3 | |
|---|---|---|
| Compression | Container — any codec | Lossy |
| Transparency | Depends on codec | n/a |
| Typically used for | Archival video, multi-language releases | Music, podcasts, anything that must simply play |
What changes when you convert MKV to MP3
Only the sound is kept
This takes the audio track out of the MKV and writes it as MP3. The picture is discarded entirely, and no conversion back will return it — keep the MKV if you still need the video.
This is a re-encode, not a repackage
Some tools can move a stream into a different container untouched when the codecs happen to line up. We do not — every job here is decoded and encoded again, so the conversion takes time in proportion to the length of the file and costs a small amount of quality even where a repackage would have been possible. In exchange the output is predictable: it plays everywhere, rather than inheriting whatever the source happened to contain.
What your MP3 will contain
The output is MP3 — written by LAME, the reference MP3 encoder, at 192 kbps by default. That sits comfortably above the point most people stop hearing a difference on ordinary equipment, and the bitrate is adjustable from 32 up to 320 if you want the file smaller or the quality nearer the source.
Other Matroska (MKV) conversions
Other ways to get MP3
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