Convert MP4 to MP3 online
Extract the audio from an MP4 video and download it as MP3, processed entirely in your browser — the file is never uploaded to a server.
or click to select it
Convert an MP4 video into an MP3 audio file without installing any software or uploading the file to a server — the whole process happens in your own browser.
Strips the video portion and keeps only the audio from the MP4 file, encoding it as MP3, a compressed audio format supported by virtually every player.
Use cases
- Extract the music from a video to listen to offline.
- Save the audio from a recording or interview in a lightweight format.
- Convert downloaded videos to MP3 to play on a device that doesn't support video.
How it works
- 1
Upload your MP4 video
Drop the file in or select it from your device.
- 2
Click Convert
ffmpeg.wasm extracts the audio track directly in your browser.
- 3
Download the MP3
Once it's done, download the resulting audio file.
Technical details
Uses ffmpeg.wasm, a WebAssembly build of FFmpeg running inside a Web Worker in your browser. The first conversion downloads the engine (around 7 MB); later conversions in the same session are faster since it's already loaded. On lower-powered devices the process may take a bit longer.
Frequently asked questions
Does converting lose quality?
The resulting MP3 uses a high encoding quality, good enough for most uses; since it's lossy compression, it isn't an exact copy of the original audio.
Is there a file size limit?
Videos up to 300 MB work reliably on most devices; larger files may exhaust the browser's available memory.