MP4 to MP3 Converter
Convert MPEG-4 Part 14 (MP4) to MPEG-1 Audio Layer III (MP3) online for free. Runs 100% in your browser. Files never leave your device. No signup, no watermarks, no limits.
Drag & drop files here, or browse
Processed on your device. Nothing is uploaded
Automate this. An open tab can convert whole folders via the Local API - still zero uploads.
Local API →How to use MP4 to MP3 Converter
- 01Add files
Choose files or drop them here
- 02Settings
Settings · Runs on your device
- 03Download
Processed on your device. Nothing is uploaded
What is a MP4 (MPEG-4 Part 14) file?
MP4 is the most universal video container, typically holding H.264/H.265 video and AAC audio. It plays on virtually every device, browser and platform.
- Developed by
- Moving Picture Experts Group (MPEG)
- Initial release
- 1999
What is a MP3 (MPEG-1 Audio Layer III) file?
MP3 is the world's most compatible lossy audio format. It compresses audio to a fraction of its original size while keeping quality most listeners find indistinguishable.
- Developed by
- Fraunhofer IIS
- Initial release
- 1993
Frequently asked questions
How do I convert MP4 to MP3?
Click “Choose Files” or drag your MP4 file onto the page, optionally adjust the settings, then hit Convert. Your MP3 file downloads straight from your browser. Nothing is uploaded anywhere.
Is this MP4 to MP3 converter free?
Yes, completely free with no hidden limits, watermarks or signup. Because all processing happens on your own device, there are no server costs to pass on to you.
Are my files uploaded to a server?
No. The conversion engine runs entirely in your web browser using WebAssembly. Your files never leave your device. You can even disconnect from the internet after the page loads and keep converting.
Is there a file size limit?
We impose no fixed limit. The practical ceiling is your device's free memory, since processing happens locally. Most conversions work comfortably with files up to a few hundred megabytes, and image or document conversions handle much more.
Does it work on my phone?
Yes. The converter runs in any modern browser on Windows, macOS, Linux, Android and iOS. No app installation is required.