WAVE MP4
MKV · to · MP3

Convert MKV to MP3 - extract audio

Pull the audio out of an MKV as an MP3 file. Wave decodes only the audio track - the video is discarded - and re-encodes to 192 kbps MP3 with LAME. Everything happens locally.

Under the hood

What actually changes

MKV source VIDEO - AUDIO AAC / AC-3 MP3 audio only AUDIO MP3 @ 192 kbps EXTRACT + ENCODE audio decoded, re-encoded
Only the audio track is pulled out and re-encoded with LAME.

MKV audio tracks are usually AAC, AC-3, DTS, or FLAC. MP3 is a different codec entirely, so extraction is always a re-encode. Wave uses libmp3lame - the reference-quality open-source MP3 encoder - at 192 kbps CBR joint-stereo.

Because Wave never has to touch the video track, the extract is fast - often 10× faster than a full MKV-to-MP4 video conversion. An hour of typical MKV audio finishes in well under a minute on a modern laptop.

How to convert

Three steps.

  1. 01

    Step 1

    Drop the MKV file onto the card.

  2. 02

    Step 2

    Pick MP3 as the output format.

  3. 03

    Step 3

    Convert and save the MP3.

FAQ

Answers, specifically.

Which audio track gets picked if the MKV has several?

The default track, which the source file marks. If the MKV has no default flag, Wave picks the first audio stream.

Will AC-3 or DTS lose quality?

They're surround-encoded - Wave downmixes to stereo before re-encoding to MP3. The MP3 sounds like a good stereo mix, not a surround field.

Can I extract as FLAC or WAV instead?

No - MP3 is the only audio output Wave produces. If you need a lossless working file, run the MP3 through a dedicated audio tool afterwards. Wave stays focused on video → MP4 with MP3 as the single audio shortcut.

Can I extract only a segment?

Not yet. Wave extracts the entire audio track; trimming lands in a later release.

How big will the MP3 be?

192 kbps works out to roughly 1.4 MB per minute - an hour of MP3 is about 85 MB.

Related

Other converters.