Extract Audio from MP4 as MP3, Free and Private

Extract the audio track from an MP4 video as an MP3 file, entirely in your browser.

Universal File Converter: Private & Fast

Convert images, videos, audio, and documents directly in your browser. Your files never leave your device, ensuring 100% privacy and security.

Video & Audio Converter

Extract audio from video or convert audio files between popular formats.

Drop your file here, or browse

Maximum file size: 50 MB

Supported: MP4, MOV, AVI, WEBM, MKV, MP3, WAV, FLAC, M4A, OGG

Output format

Advanced Media Tools

Extract Audio Trim Video

100% In-Browser Processing

Your files are processed strictly in local device memory. Nothing is uploaded — see how, and check for yourself.

How It Works

How to convert files with DuckConvert

Select Your File

Choose the file you want to convert from your device or drag and drop it into the converter.

Choose Output Format

Select your desired output format and any specific settings for your conversion.

Convert & Download

Click "Start Conversion" and wait for the local process to finish, then download your new file.

Don't take our word for it

This conversion runs entirely in your browser — nothing is uploaded. See exactly how, and check for yourself using your browser's DevTools Network tab.

How It Works

Conversion Mechanics

Whether you're pulling a podcast recording out of a screen-captured video, saving a lecture's audio to listen to offline, or grabbing a song from a music video, this strips the video track and keeps just the audio, encoded as a standard MP3. The whole conversion runs through an in-browser build of FFmpeg, so even long recordings process without the video ever leaving your device. For a dedicated audio-extraction workflow with more format options, see DuckConvert's Extract Audio tool.

Why It's Private

Runs Entirely In Your Browser: Files are decoded and re-encoded strictly in local memory.
No Network Requests: The converter makes no calls to any server — check your browser's DevTools Network tab to confirm.
Nothing to Sign Up For: No account, no upload, and no server-side storage of your files.
Runs On Your Hardware: Processing uses your own device's CPU via Web Workers, not a remote server.

Step-by-Step MP4 to MP3 Local Guide

Select File

Drop your .mp4 file into the box above.

Configure

Confirm MP3 is selected as the output format.

Convert

Click Convert — the audio track is extracted and encoded locally.

Save Result

Download the resulting .mp3 file.

Frequently Asked Questions on Secure MP4 to MP3 Conversion

The audio track's own bitrate matters more than the video quality — most MP4s have a perfectly usable audio track regardless of video resolution.

Extraction is much faster than full video transcoding since the audio track is just being pulled out and re-encoded, but very long files still take proportionally longer on slower devices.

Not on this page — it extracts the full track. Trim the video first with DuckConvert's Trim Video tool if you only need a section.