Extract audio from video

M4A copies the original AAC track untouched (instant); MP3 re-encodes at ~55× realtime for maximum compatibility; WAV gives you uncompressed PCM for editing.

Frequently asked questions

Which format should I pick?

M4A if you just need the audio file (it's the original data, instant, zero loss). MP3 if the target app is old or picky — it's re-encoded but universally supported. WAV if you're editing the audio afterwards and want uncompressed samples.

Why is M4A instant?

Most video audio is already AAC — M4A is just AAC in an audio-only container. The packets are copied without touching a codec, so a 1 GB movie's audio extracts in seconds.

Is there a length limit?

No. MP3 encoding runs at roughly 55× realtime, so even a 3-hour recording takes a few minutes. Everything streams from disk with flat memory.

Related tools