MP4 to MP3 Converter

Extract audio from video files and save it as MP3. Convert MP4, MOV, WebM, MKV and AVI to MP3 locally in your browser — private, free, no upload.

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MP4 · MOV · WebM · MKV · AVI

No upload required100% free foreverWorks in your browser
How it works

MP4 to MP3 Converter for private browser workflows

Extract audio from any video

Select a video file and choose MP3 as the output format. LessMB extracts the audio track and encodes it as a standard MP3 file that plays everywhere.

Multiple input formats

Works with MP4, MOV, WebM, MKV and AVI sources. The audio track is transcoded to MP3 regardless of the source container or codec.

Private local processing

Audio extraction runs entirely in your browser. Interviews, lectures and personal recordings are never uploaded to a server.

Common use cases

Save audio from recorded lectures, webinars and video podcasts as portable MP3 files.

Lectures and podcasts

Extract audio tracks from music videos and live performances for offline listening.

Music from videos

Pull voice audio from screen recordings and video messages for easier sharing.

Voice memos

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FAQ

MP4 to MP3 Converter FAQ

Answers for the most common questions about this tool, supported workflows, and local browser processing.

No uploadFree toolBrowser-based
Can I convert video to MP3 for free?

Yes. LessMB extracts MP3 audio from video files for free, directly in your browser.

Which video formats can I convert to MP3?

MP4, MOV, WebM, MKV and AVI are supported as input formats.

Is the audio quality preserved?

The audio is transcoded to MP3 at a practical bitrate. For most speech and music content the quality is very good.