MP4 to MP3 Converter
Pull the audio out of any video and save it as an MP3. Lectures, interviews, music performances, voice notes recorded as video – drop the file in, pick a bitrate, and download the MP3 in seconds. The conversion runs on your device using FFmpeg in your browser, so nothing is uploaded.
Supports MP4, MOV, MKV, WebM, AVI, M4V and most audio formats as input.
How to convert MP4 to MP3
Add your video (up to 300 MB per file).
Choose an audio bitrate – 192 kbps is a good default.
Click Convert and download the MP3.
Why use the Convert Now mp4 to mp3 converter
Real FFmpeg
The same encoder professionals use, running privately in your browser.
Choice of bitrate
128 kbps for speech, 192 for general use, 320 for music.
Batch extraction
Convert several videos in one go.
No upload, no queue
Starts immediately – no waiting for a server.
How audio extraction works
A video file is a container holding separate video and audio streams. Converting MP4 to MP3 discards the video stream and re-encodes the audio into MP3, a format every phone, car stereo and media player understands. Because only the audio is processed, extraction is fast – usually a few seconds for a typical clip.
Choosing a bitrate
128 kbps produces small files and is perfectly clear for speech, podcasts and lectures. 192 kbps is transparent for most music on ordinary headphones. 320 kbps is the highest MP3 quality and is only worth the extra size for music you will listen to critically. Note that MP3 cannot add quality the original did not have – if the video's audio is 128 kbps AAC, choosing 320 just makes a bigger file.
Read the guide: How to Make a GIF from a Video (Free, No Watermark)
Frequently asked questions
How do I convert MP4 to MP3 for free?
Add the video above, choose a bitrate and click Convert. The MP3 downloads directly – no account or watermark.
Is my video uploaded?
No. FFmpeg runs inside your browser and the file stays on your device.
What is the maximum file size?
300 MB per file. Larger videos can be compressed first with the Compress Video tool.
Which formats can I extract audio from?
MP4, MOV, MKV, WebM, AVI, M4V, and audio files such as M4A, WAV and OGG.
Why is the first conversion slow to start?
The video engine (about 30 MB) downloads once per session and is then cached.
Does it work on iPhone and Android?
Yes, in Safari and Chrome. Very long videos take longer on phones.
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