ALL VIDEO TOOLS23
Extract Audio
Extract Audio from Video — Free, No Upload Required
Pull the audio track out of MP4, WebM, MOV, AVI or MKV — losslessly, or as MP3 or WAV.
About Extract Audio
A video file is a box with separate streams inside it, and the audio is one of them. Getting it out does not require converting anything: FFmpeg can lift the encoded audio track from the container and write it into a new one without decoding a single sample, which takes milliseconds and is bit-for-bit lossless. That is what this tool does by default, and the page tells you afterwards whether the copy actually happened rather than promising it in advance. What you get back is the track in whatever codec the video was carrying — usually AAC from an MP4 or MOV, Opus or Vorbis from a WebM — in a container that matches. That is the right choice when you want the audio itself: a lecture to listen to, a podcast track pulled from its video version, a piece of music from a performance recording. The other two arms decode that track and encode it again. Choose MP3 when the file has to play on absolutely anything, at a bitrate no higher than the video's own audio track — going above it buys nothing. Choose WAV when the audio is heading into an editor, a transcription tool or a DAW that wants uncompressed samples. Both are re-encodes and both cost a generation of quality, which is why they sit behind a named choice rather than happening silently. FFmpeg runs as WebAssembly inside your browser and the video is never uploaded.
Questions
What does the Keep original setting actually do?
It runs a stream copy: FFmpeg lifts the encoded audio track out of the video container and writes it into a new one without decoding a single sample. Nothing is re-encoded, nothing is lost, and it takes milliseconds — 29 milliseconds on the clip this was measured against. The page reports what the run actually did afterwards, rather than promising it in advance.
What format do I get from Keep original?
Whatever the video was already carrying. That is usually AAC from an MP4 or a phone recording, and Opus or Vorbis from a WebM. You are getting the same bytes the video held, in a container that can hold them — which is exactly why the run costs nothing in quality.
Should I pick MP3 or WAV instead?
MP3 when the file has to play on absolutely anything, and no higher than the video's own audio bitrate — going above it buys nothing. WAV when the audio is heading into an editor, a DAW or a transcription tool that wants uncompressed samples. Both decode the track and encode it again, so both cost a generation of quality; that is why they sit behind a named choice.
Is there a size limit on the video?
No, and it is not a courtesy: the video is mounted into the FFmpeg engine rather than read into the tab, so a large source costs no memory at all — that path has been verified end to end at 2500 MB. What does have to fit in the tab is the audio that comes out, which matters mainly on the WAV setting at roughly 10 MB per minute.
Which video formats can I use?
MP4, WebM, MOV, AVI and MKV. The demuxer is chosen from the file's own extension, so keep it intact — a renamed or extension-less file leaves the engine guessing.
Is my file uploaded to a server?
No. Transmute processes everything locally in your browser using JavaScript and WebAssembly. Your files never leave your device — there is no server, no upload, no cloud processing.