Input
MP4, MOV and WebM containers with an audio track this browser can decode.
Local media tool
Convert MP4 to MP3 privately in your browser.
Extract the main audio track from an MP4, MOV or WebM video. Your media stays on this device while the browser creates the MP3.
- No account
- No media upload
- Processed on this device
How to convert MP4 to MP3
- 01
Choose one video
Select an MP4, MOV or WebM file from this device.
- 02
Pick the MP3 quality
Use 192 kbps for a balanced default, or choose 128 or 320 kbps.
- 03
Download the MP3
The browser extracts the main audio track and keeps the result locally for 30 days.
Formats, quality and limits
Output
One MP3 at a fixed 128, 192 or 320 kbps. No trimming or audio enhancement.
Limits
One local file, up to 300 MiB and 20 minutes. The main audio track is used.
The video is processed locally
The source video, decoded audio and MP3 are not uploaded to a Whisper Web application server. The page and MP3 engine still need to be downloaded, so this is not a promise of complete offline use.
Container support does not guarantee every codec
MP4, MOV and WebM can contain different audio codecs. The converter checks the real container and main audio track before it starts. If this browser cannot decode that track, re-export the video or try another current browser.
MP4 to MP3 questions
Does Whisper Web upload my video?
No. A local file is read and converted in this browser. Ordinary requests are still made to load the website, analytics and the MP3 engine.
Which MP3 quality should I choose?
192 kbps is the balanced default. Choose 128 kbps for a smaller file or 320 kbps when a larger file is acceptable.
Can I choose a different audio track?
Not in this version. The converter uses the video's main audio track and downmixes audio above two channels to stereo.
Why can a supported video still fail?
A supported container may contain an audio codec your browser cannot decode, or the file may be damaged or incorrectly named.
How long is the MP3 kept?
A successfully saved MP3 stays in this browser for 30 days, unless the browser or user clears site data sooner. Download files you want to keep.