MP4 to MP3 Converter

mp4 → mp3

Pulls the audio track out of an MP4 as a 192 kbps MP3, decoded and encoded in your browser. The video file is not uploaded.

QueueNothing is uploaded

Drop an MP4 file here

or click to browse your device

Processing video…

About this MP4 to MP3 converter

This tool reads the audio track out of a video file and re-encodes it as an MP3. Your browser decodes the track with its built-in audio decoder, and the LAME encoder turns the samples into a 192 kbps stereo MP3 inside a background worker. The video itself is never opened for playback or altered; only the sound comes out the other end.

Encoding usually finishes well before the video would finish playing, since your processor is not limited to real-time speed the way playback is. A phone takes longer than a laptop, but the work still happens on the device, not on a server.

How to use it

01

Add your video

Drop an MP4 file on the box, or click it to browse your device.

02

Convert

Click Convert to MP3. Your browser starts decoding the audio track right away.

03

Wait for it to finish

A progress bar tracks the encoding. Most clips finish in a few seconds; long files on a phone take longer.

04

Get your MP3

When the conversion finishes, the MP3 appears with a Download button. Nothing is saved to your device until you click it.

What it does

  • Your browser decodes the video's audio track, and the LAME encoder writes a 192 kbps stereo MP3, all inside this tab.
  • The video itself is never opened for playback or altered. Only the sound is read out of it.
  • Encoding runs in a background worker, so the page stays responsive while a long file processes.
  • The finished MP3 waits behind a Download button, so nothing is saved until you ask for it.
  • One video at a time, up to 100 MB.

Specifications

Specification Details
Accepts Video files your browser can decode, one at a time
Output 192 kbps stereo MP3 at 44.1 kHz
Video track Discarded. Only the audio comes out.
Decoding Your browser's built-in audio decoder
Encoding LAME (lamejs 1.2.1) in a Web Worker, loaded from the cdnjs CDN
File size limit 100 MB per video
Where your video goes Nowhere. It stays in this tab's memory.
Good to know

What this converter does not do

It only pulls out the sound. For anything else, one of the other tools fits better.

Fixed bitrate

Every file comes out as a 192 kbps MP3. There is no setting for a smaller or larger file.

One audio track only

A video with several language tracks gives you whichever one your browser's decoder picks, with no way to choose.

No trimming

You get the full length of the recording and cut it afterwards in an audio editor.

No tags or cover art

Only the audio samples come through. Titles, artist names and chapter marks are not carried over.

Related tools

MOV to MP4 QuickTime recordings into a format everything plays. Video converter Convert, re-encode, or pull the audio out. Audio converter Batch convert between the four common audio formats. Vocal remover Separate vocals from the backing track for karaoke.
All audio and video tools → What that 192 kbps MP3 actually costs you →

Frequently asked questions

A little. The track is decoded and re-encoded as a 192 kbps MP3, and MP3 is lossy, so it can't be bit-for-bit identical to the original. At that bitrate the difference is hard to hear on ordinary headphones.

Each video can be up to 100 MB. The whole file is read into memory before decoding starts, so a long recording can fail on a phone or another low-memory device.

No. The audio track is decoded and encoded to MP3 entirely inside your browser. The only thing downloaded is the MP3 encoder itself, from the cdnjs CDN.

Anything your browser's own decoder can open, which in practice means ordinary MP4 or MOV files with AAC audio. Unusual codecs, DRM-protected files and some MKV or AVI containers will not decode.

No, every file is encoded at a fixed 192 kbps. For control over the encode, a desktop tool such as ffmpeg is the better choice.

Your video stays on your device

Your browser decodes the audio track and encodes the MP3 inside this tab. The video file itself is never uploaded. The only network request is the one-time download of the MP3 encoder library, from the cdnjs CDN.