Convert MP4 to MP3, Free
Upload your MP4 file and get a MP3 in seconds. No account, no watermark.
How to convert MP4 to MP3
MP4 video files contain both a video track and an audio track. When you only care about the audio, whether it is a recorded lecture, a podcast episode saved as video, a music video, or a meeting recording, you can strip out the video and save just the audio as an MP3 that is far smaller and plays on any device.
BoltConverter extracts the audio from your MP4 and encodes it as an MP3 at 192 kbps, which is high enough for music and voice recordings to sound excellent. The conversion runs on our servers, handles large files reliably, and deletes your file the moment you download the result.
Upload your MP4
Drag the MP4 file onto the upload area or click to browse. Files up to 2 GB are accepted.
Click Convert
Hit Convert. The server extracts the audio track and encodes it as a 192 kbps MP3.
Wait for processing
Most conversions complete in 30 to 60 seconds. Longer videos take more time.
Download your MP3
Click Download to save the MP3. The MP4 and the output file are deleted from our server immediately.
Frequently asked questions
Will the audio quality be the same as in the MP4?
The output quality matches the audio track in the original MP4. Converting from a high-quality source gives you a sharp 192 kbps MP3.
What is the maximum file size for MP4 uploads?
BoltConverter accepts MP4 files up to 2 GB.
Can I extract audio from a long video?
Yes. Long recordings like lectures, interviews, or meetings are handled the same as short clips. Processing time scales with file duration.
Is the video file deleted after conversion?
Yes. Both the original MP4 and the converted MP3 are deleted from our servers as soon as you download.
Can I also convert MOV or AVI files to MP3?
Yes. BoltConverter supports audio extraction from MOV, AVI, MKV, WebM, and other video formats. See the full list of audio converters.
Is it free?
Yes, completely free. No account needed and no cap on how many files you convert.