Extract Audio from Video

How it works

Video files store their audio as an independent track inside the same container as the picture. This tool reads the file's metadata to find exactly where that audio track's bytes live, then copies them into a fresh, audio-only file — no decoding, no re-encoding, no quality change from the source. If the audio is a compressed codec like AAC (the overwhelming majority of MP4/MOV files), the result is a standard .m4a file. If the source audio is raw, uncompressed PCM — common in some screen recordings and camera formats — it's wrapped in a .wav file instead, since there's no compressed stream to package as .m4a.

Limitations

This extracts the first audio track only. Supported containers are MP4, M4V and MOV; WebM and Matroska (MKV) aren't supported yet. If you specifically need an .mp3 file, run the result through a dedicated audio converter — producing MP3 requires re-encoding, which this tool deliberately avoids to keep the extraction instant and lossless.

FAQ

Is this the same as "MP4 to MP3"?

The goal is the same — get just the sound out of a video file — but this tool doesn't convert to MP3. It copies the original compressed audio (usually AAC) into a .m4a file with no re-encoding, which is instant and lossless. Converting to MP3 specifically would mean decoding and re-encoding, which takes time and always loses a little quality; if you specifically need an .mp3 file, use a dedicated audio converter afterward.

What about videos with uncompressed (PCM) audio?

Some cameras and screen recorders store audio as raw, uncompressed PCM samples rather than a compressed codec. Those get wrapped in a .wav file instead of .m4a — a bare .m4a container needs a real compressed elementary stream to make sense, and PCM audio doesn't have one. Either way, nothing is re-encoded; the audio samples are identical to the source.

Is there a file size limit?

No. Because the audio is copied rather than decoded, extracting from a multi-gigabyte video costs about the same as a small one — there's no server-side processing to ration.

Is my video uploaded anywhere?

No — this runs entirely in your browser. Only the small metadata region and the audio track's own bytes are ever read from your file.