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MP4
MP3

MP4 to MP3 Converter

Pull the audio out of any MP4 video and save it as an MP3 - free, private, runs in your browser.

Drop one or many - all convert to MP3. Per-row progress, batch convert, ZIP download.

Why convert MP4 to MP3?

Extracting the audio track from an MP4 is one of the most common conversions on the web: people want the audio from a lecture, podcast interview, concert clip, or YouTube download they can listen to on a phone or car stereo without the video overhead. An MP3 is also dramatically smaller than the original MP4, making it easy to share over email or messaging.

Under the hood this is a real re-encode, not a remux - we read the AAC (or occasionally MP3) audio track inside the MP4 container, decode it to raw PCM, and re-encode it to MP3. There's a small quality cost from the second lossy pass, but at 192 kbps and above it's imperceptible in typical speech and music. Everything happens in your browser using WebCodecs - the MP4 file is never uploaded.

The "MP4 to MP3" search is really a family of similar intents. Some people want the audio off a downloaded video. Some want a podcast episode they can play in the car. Some are stripping music from a TikTok or Instagram Reel they saved. Some are reusing audio from a film or TV clip for an academic project. The conversion is the same in every case; the right defaults vary - the choices we ship (192 kbps CBR, full sample rate) are the sweet spot for that wide audience.

A note on legality: extracting audio from a video you own or have the right to use is fine. Stripping the audio from copyrighted YouTube or Spotify content for redistribution is not - even when the technical conversion is identical. We make no judgement about the file you drop in (we can't - it never leaves your device), but it's on you to know whether what you're doing is allowed.

Performance notes: a 60-minute lecture MP4 converts in about 30-60 seconds on modern desktop hardware. Mobile Safari is roughly 2-3x slower than desktop Chrome for the same input. Firefox is slightly slower than Chrome on first conversion because we lazy-load a ~100 KB LAME encoder for MP3 output; after that download it's cached for the session.

Common MP4 to MP3 use cases

  • Lectures, talks, and podcasts

    Strip a recorded lecture down to its audio so you can listen during commute or while exercising. MP3 is small enough to email to a study group or upload to a private podcast feed.

  • Voice memos and meeting recordings

    Zoom and Teams export MP4. If you only need the audio for a transcript or a follow-up review, MP3 cuts the file size by 90% with no useful loss.

  • Music ripped from a video source

    You bought a digital concert film or live-show video and want the audio standalone for your music library. MP3 at 192 kbps is the safe choice; for archival, use WAV instead.

  • Reusing dialogue or sound effects

    Pull a single line from a movie or TV clip for a remix, mashup, or educational project. The MP3 output drops into any DAW or video editor.

  • Transcription input

    Most speech-to-text tools accept MP3 directly and produce identical transcripts to MP4 inputs. Going to MP3 first cuts upload time substantially.

  • Sharing a clip on chat or email

    A 100 MB MP4 won't make it through most email filters. The equivalent 8 MB MP3 sends cleanly through Gmail, Slack, and most enterprise email systems.

MP4

About MP4

MP4 is the most widely supported video container, based on the ISO Base Media File Format. It can carry H.264, H.265 and AV1 video with AAC, MP3, or Opus audio.

MP3

About MP3

MP3 is the most compatible lossy audio format - 30+ years old, plays on literally everything from car stereos to podcast apps.

How to convert MP4 to MP3

  1. 01

    Drop your MP4 file

    Drag a MP4 onto the converter above, or click the box to pick one from your device.

  2. 02

    MP3 is already selected

    We've preselected MP3 as the output format. Change it from the dropdown if you want a different target.

  3. 03

    Convert and download

    Click Convert and wait for the progress bar to finish. Download the MP3 when it's ready.

MP4 to MP3 FAQ

See all formats →