Is ConvertMP4 free?
The converter is intended to be free to use. The site may support itself with advertising.
Are my videos uploaded?
The converter is designed to process the selected file locally in your browser rather than sending the video to a conversion server.
Can I convert any MP4?
No. MP4 is a container, and the browser still needs to decode the audio track inside the file. Files with unsupported audio codecs may fail.
Why is the conversion slow?
Decoding and encoding happen on your device. Large files, long videos, limited memory, and heavy CPU use can increase conversion time.
Why did my browser tab become slow?
Local media processing can use substantial CPU and memory. Try closing other demanding tabs and use a smaller file.
Can I choose MP3 quality?
Yes. The converter exposes several MP3 bitrate choices. Higher bitrate generally means a larger output file.
Is WAV better than MP3?
They are designed for different needs. MP3 is compressed and smaller; WAV commonly stores uncompressed PCM and is much larger. See the MP3 vs WAV guide.
Does the site work on phones?
The interface is responsive, but large audio conversions can be demanding on mobile devices. Desktop browsers may provide more memory and processing headroom.
What should I do if conversion fails?
Confirm the file is a valid MP4 with an audio track, refresh the page, and try a current browser. If one MP4 fails while another works, the first file may use an unsupported codec or be damaged.