Browser FFmpeg recipe
Convert MP4 to MP3 Online with FFmpeg
Create an MP3 audio file from the video track in an MP4 file.
Command
Run this FFmpeg command
ffmpeg -i input.mp4 -vn -ar 44100 -ac 2 -b:a 192k output.mp3When to use it
- podcast clips
- voice notes
- music from video
- quick audio extraction
How it works
- Upload your MP4 file in FFmpeg Web.
- Use the prefilled command to remove video and encode the audio as MP3.
- Run the command and download the generated MP3 file.
Option reference
| Option | What it does |
|---|---|
-vn | Removes the video stream. |
-ar 44100 | Sets a standard 44.1 kHz audio sample rate. |
-ac 2 | Outputs stereo audio. |
-b:a 192k | Uses a 192 kbps audio bitrate. |
Practical notes
- For smaller audio files, lower the bitrate to 128k.
- For speech-only files, mono audio with -ac 1 can reduce the file size.
FAQ
Does this upload my video to a server?
No. FFmpeg Web runs in your browser with WebAssembly, so the file is processed locally.
Can I change the MP3 quality?
Yes. Change -b:a 192k to a lower or higher bitrate such as 128k or 256k.