How long does conversion take?

Audio extraction is usually faster than real-time. ffmpeg.wasm is downloaded once (~25 MB) and cached by the browser.

Is my video uploaded?

No — ffmpeg.wasm runs inside your browser. The MP4 is processed locally and discarded as soon as you close the tab.

Which bitrate should I choose?

192 kbps is transparent for speech and most music. 128 kbps is fine for podcasts. 320 kbps for archival quality.

MP4 to MP3 Converter

Extract the audio track from any MP4 video as an MP3 file. Useful for podcast clips, music videos, lecture recordings, and voice memos exported as video. Runs entirely in your browser.

100% in your browser. Your file never leaves your device.

MP4 video file

MP3 bitrate

Pick an MP4 file to begin.

How to convert MP4 to MP3

Pick your .mp4 file.
Choose the MP3 bitrate (192 kbps is a good default).
Press Extract MP3 and download.

Common use cases

Podcasting: isolate the audio track from a video interview for hosting on Spotify/Apple Podcasts.
Voice memos: iPhone screen recordings produce MP4 — pull out the audio for transcription.
Lectures & talks: turn recorded video lectures into MP3 audiobooks for offline listening.

Related: FLAC to MP3 · WAV to MP3 · OGG to M4A · Audio Converter

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