Convert Matroska (MKV) to M4A
Free online converter for Matroska (MKV) files. AAC audio in an MP4 container. Nothing to install, no watermark, and every file is deleted automatically.
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Upload a Matroska (MKV) file to convert it to M4A. 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 M4A
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
M4A .m4a
An MPEG-4 container holding audio only — usually AAC, sometimes lossless ALAC. The extension tells you the wrapper, not the contents.
Good for
- Rich tagging, including chapters and artwork
- Holds either lossy AAC or lossless ALAC
- The standard for iTunes and Apple Music files
Trade-offs
- The extension alone does not tell you the quality inside
- Support outside Apple platforms is inconsistent
audio/mp4
MKV and M4A side by side
| MKV | M4A | |
|---|---|---|
| Compression | Container — any codec | Container — usually lossy AAC |
| Transparency | Depends on codec | n/a |
| Typically used for | Archival video, multi-language releases | Apple audio, audiobooks, podcasts |
What changes when you convert MKV to M4A
Only the sound is kept
This takes the audio track out of the MKV and writes it as M4A. 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 M4A will contain
The output is AAC — the same codec a bare .aac file holds, wrapped in an MP4 container so that artwork and tags have somewhere to live.
Other Matroska (MKV) conversions
Other ways to get M4A
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