How to Use the Extract Audio from Video (MP4 to MP3)
- Select the video file you want to extract audio from.
- Wait for the in-browser video engine to load on first use.
- Click Extract to pull out the audio track.
- Download the resulting MP3 file.
Frequently Asked Questions
Is my video uploaded to a server?
No. ffmpeg.wasm processes the video entirely in your browser, so the file never leaves your device.
Why is there a large download on first use?
The tool loads a WebAssembly build of FFmpeg (roughly 25-30 MB) the first time you use it. It's then cached, so later conversions start faster.
What file size works best?
Because processing happens on your device, this works best for files under about 100 MB. Very large videos may be slow or run out of memory, especially on phones.
Which video formats are supported?
Common formats like MP4, MOV, WebM and MKV work for extracting audio.