Do you upload my videos to a server?

No. All processing happens locally in your browser using WebAssembly. Your files never leave your device.

Does it work with MKV and MOV too?

Yes. You can extract audio from MP4, MKV, and MOV and save it as MP3.

What bitrate should I use for dialogue?

96 kbps mono is ideal for spoken word. If there’s background music, try 128 kbps stereo.

MP4 to MP3 Converter (Free & Online)

Extract audio from MP4, MKV, and MOV videos — right in your browser. No uploads, 100% private, fast conversions with WebAssembly.

Convert MP4 to MP3 instantly (files never leave your device)
Batch process multiple videos and download as ZIP
Perfect for podcasts, lectures, voice notes, and music

Start converting ↓

Upload and Convert Your Audio Files

⬆️

Drag & drop files here or click to select

Supported input(max 100 MB)

MP4 MOV MKV

MP3 OGG WAV AAC M4A FLAC

Output Format

Bitrate

Sample Rate

Channels

Compression Mode

Normalization

Fades

How to Convert MP4 to MP3

Drag & drop your MP4, MKV, or MOV files into the box above.
Set the output format to MP3 (it’s preselected by default, but you can choose another).
Choose bitrate and channels (see recommendations below), then click Convert Files.

Why Convert MP4 to MP3?

MP3 files are smaller and easier to share or edit. Extract just the audio from your video to create podcast episodes, study notes, or music-only tracks without re-uploading anything to a server.

MP4 to MP3 — FAQ

Popular Conversions

Quick links to our most popular audio conversion tools:

We use cookies for analytics and ads to improve your experience and to help keep Free Audio Converter Online 100% free. You can accept all, reject all, or choose preferences. Learn more.