MP4MPEG-4 Part 14
The most compatible video format, played by almost every phone, computer, TV and social network.
Convert MP4 to MP3
Turn your MP4 videos into MP3 files right in your browser, so your files are never uploaded to a server. How long it takes depends on the video’s length and your device.
- Files never uploaded
- Free, no sign-up
- No queue
MP40000002066747970
MP34944330400000000
The first bytes of a file often reveal its real format.
or drop them here. You can also paste an image (Ctrl+V).
Free · No sign-up · No upload
Files
These sample files are generated on the page. Convert them to try it out, or add your own.
How to convert MP4 to MP3
- 01
Add your MP4 files
Click “Choose MP4 files” or drop them on the page. You can add several at once.
- 02
Check the MP3 format
MP3 is already selected. Choose the bitrate, from 128 to 320 kbps.
- 03
Convert and download
Click “Convert”, then download your MP3 file. With several files, grab everything at once as a ZIP.
MP4 to MP3: what to know
Extracting the sound from an MP4 lets you listen again to a lecture, a talk, an interview filmed on a phone or a concert. The browser reads the file and decodes only the soundtrack, leaving the picture untouched, then encodes it as MP3. A 48 kHz soundtrack, the video standard, is resampled to 44.1 kHz; 5.1 sound is mixed down to stereo, without the bass channel (LFE), and a mono track stays mono.
A video’s soundtrack is already compressed, usually as AAC. The default 192 kbps setting therefore works very well; going up to 320 kbps adds little, since the source has already lost some detail. For a talk or a lecture, 128 kbps is enough. The MP3 is created without tags and takes the video’s name, for example lecture.mp3 for lecture.mp4.
MP4 vs MP3: what’s the difference?
MP3MPEG-1 Audio Layer III
The most universal audio format. Its compression shrinks files a lot while keeping good listening quality, and it plays on every device.
- Compression
- Lossy
MP4 to MP3: frequently asked questions
Can I extract the audio from an MP4 video that lasts several hours?
Yes, but allow for memory. The whole video file is read, then the entire soundtrack is decoded before encoding: one hour of stereo sound takes up more than 1 GB once decoded. A recent computer usually copes; on a phone, split the video first or stick to shorter recordings.
Why can’t the sound of my MP4 video be decoded?
Most often the video simply has no audio track, which is the case for many screen recordings and for clips exported without sound. Less often, the audio uses a codec your browser cannot read. Check in a media player that the video really has sound, then try another browser if needed.
Are my MP4 files uploaded to the internet?
No. The file is read and converted by your browser, on your device. Nothing is sent to a server, and nothing is kept after you close the page.
Does converting MP4 to MP3 reduce quality?
Only the audio track is extracted, then encoded as MP3. At the default bitrate (192 kbps) quality is very good for listening; choose 320 kbps for the maximum.
How many MP4 files can I convert?
As many as you like, for free and without signing up. Add them all, then download the results one by one or in a single ZIP. The maximum size depends on your device and browser, with a few caps that protect its memory (for example 20,000 files per archive or 5 million filled cells per workbook: see the home page FAQ); a file over one of them is not converted, and a message says so.
Does it work on iPhone and Android?
Formatomat is designed for recent browsers on computers, iPhone and Android, with no app to install. A conversion the browser cannot do (a format it cannot read or write) is refused with a message that says so.