Extract the audio you need
Turn a recording, interview, or lesson into an MP3 for a compatible player. The tool keeps the audio track and removes video; it is not an audio editor or a service for downloading videos from the internet.
Local processing with a clear privacy boundary
Your MP4 is read from your device and passed to a browser worker, not to an application API. The video does not leave your device. The first conversion downloads the FFmpeg runtime on demand; that runtime does not contain your file or output.
What happens during conversion
Choose an MP4, start conversion, and watch the engine's real progress. The file is decoded in memory, its audio track is extracted, and a downloadable MP3 is created. Save the result and close the tab when you are done to release memory.
Compatibility and practical limits
It works in modern browsers with WebAssembly and Web Workers. The initial limit is 200 MB to avoid exhausting memory on smaller devices. Duration and speed depend on video size, source codec, and local hardware.
A measured foundation for video and audio tools
This first tool validates a local media workflow before adding MOV-to-MP4 or AVI-to-MP4. Initial load, interaction timing, and engine performance will be measured before expanding the category.