Browser FFmpeg recipe

Convert MP4 to M4A Online with FFmpeg

Copy the audio track from an MP4 file into an M4A container.

Command

Run this FFmpeg command

ffmpeg -i input.mp4 -vn -c:a copy audio.m4a

When to use it

  • fast extraction
  • keeping AAC quality
  • voice memos

How it works

  1. Upload the MP4 file.
  2. Run the audio copy command.
  3. Download the extracted M4A audio file.

Option reference

OptionWhat it does
-vnRemoves the video stream from the output.
-c:a copyCopies the audio stream without re-encoding.
audio.m4aWrites an M4A audio container.

Practical notes

  • This works best when the MP4 audio stream is AAC or another M4A-compatible codec.
  • Use MP4 to MP3 if you need broader compatibility with older players.

FAQ

Is M4A better than MP3?

M4A can preserve AAC audio without re-encoding, while MP3 is more widely supported by older apps.

Why is this faster than MP3 conversion?

The audio stream is copied instead of decoded and encoded again.