MP4 to MP3 Converter

Convert MP4 to MP3 in your browser, with no upload

An MP4 holds two things, a picture and a soundtrack, and plenty of the time you only need the second. This page takes the MP4 you drop on it, leaves the picture alone, and encodes the soundtrack as an MP3 at the bitrate you pick.

The MP4 is opened by your own browser and the MP3 is made on your device. The file never leaves it, so a large recording does not have to crawl up a slow connection first. Free, unlimited, no signup, no watermark.

MP4 to MP3 in three steps

1. Drop the MP4 on the panel above, or choose it from your files. On a phone the picker also offers your photo library.
2. Pick 128, 192 or 320 kbps. 192 is selected for you.
3. Press Convert to MP3 and save the result. The MP3 takes the name of the MP4, with the ending changed.

How large the MP3 will be

The size of an MP3 follows from its length and bitrate alone. A 2 GB MP4 and a 200 MB MP4 of the same length give the same MP3.

What happens to the sound quality

The soundtrack of an MP4 is nearly always AAC, a compressed format. Turning it into an MP3 means decoding it and compressing it again, so a small amount is lost a second time. At 192 kbps and above that loss is very hard to hear.

A higher bitrate keeps more of what the MP4 has, but nothing can put back what its own compression removed. For a voice recording 128 kbps is plenty; for music you care about, choose 320.

What is kept from the MP4

• The whole soundtrack, start to finish, in stereo when the MP4 is stereo and mono when it is mono.
• The title and other tags the MP4 carries, copied into the MP3 where there are any.
• Not the picture, and not a second language track or commentary. For other video formats, use the video to MP3 converter.

The MP4 is never sent anywhere

MP4 files are often the private ones: a screen recording with your inbox in the corner, a call you saved, a clip of your children. Here the file is read where it sits. There is no upload, no account that ties a conversion to you, and no copy on a server to delete afterwards, because none was ever made.

MP4 to MP3 questions

How do I convert MP4 to MP3 without uploading the file?

Open the MP4 here and the conversion happens inside your browser tab. The file is read from your own disk, its audio track is encoded as an MP3 on your device, and the result is saved back to it. The MP4 is never sent anywhere, so a private recording stays private.

Does converting MP4 to MP3 lose quality?

A little, in principle. The sound in an MP4 is usually AAC, which is already compressed, and MP3 compresses it a second time. At 192 kbps and above most people cannot hear the difference. Choosing 320 kbps keeps the most of what is there, but it cannot make the MP3 better than the MP4 it came from.

How big will the MP3 be?

The size depends only on the length and the bitrate, not on how large the MP4 is. A three minute song at 192 kbps comes to about 4.3 MB. An hour of talk at 128 kbps is about 58 MB, and an hour at 320 kbps is about 144 MB.

My MP4 has more than one audio track. Which one is converted?

The default track, the one a video player picks when you press play. Most MP4 files from phones, cameras and screen recorders have a single track, so this only matters for films and recordings with several languages or a separate commentary.

Does it work with MP4 videos from an iPhone or Android phone?

Yes. Phone cameras and screen recorders save AAC sound in an MP4 or MOV file, which is exactly what this reads. On Android, open this page in Chrome. On an iPhone or iPad you need iOS 26 or later, because older Safari versions cannot decode audio in a page.

Why does it say my MP4 has no audio track?

Because the file is silent. Screen recordings made with the microphone off and some exported animations contain only a picture, so there is no sound to save. A different message names the audio format when the MP4 has sound that browsers cannot decode, such as Dolby Digital.

What does the MP4 to MP3 conversion run on?

Your device. Your browser's built-in decoder reads the sound, and LAME, the open source MP3 encoder, runs as WebAssembly in the same tab to write the MP3. That is why it needs no install and no account, and why the MP4 has nowhere to go but your own disk.