How to Convert a Video to MP3 for Free (No Software, No Upload)

A lecture recording where you only need the audio for your commute. A voice memo that your phone saved as video. An interview you want in your podcast app. Music from a screen recording of your own performance. "Video to MP3" is one of the most common conversion needs there is — and most of the tools offering it are either adware-laden desktop installers or upload sites with size limits and questionable privacy.

The browser-only way

FileLark's MP4 to MP3 converter does the extraction entirely inside your browser using ffmpeg compiled to WebAssembly — the same audio engine used by professional video software, running on your own device. Drop in an MP4, WebM, MOV, MKV or AVI; the audio track is extracted as a high-quality variable-bitrate MP3 (~190 kbps, transparent for speech and very good for music) and downloads straight away.

Because nothing is uploaded, three usual problems disappear: there is no file size cap beyond your device's memory, no queue behind other users, and no server that ever sees your recording — which matters when the video is a private meeting, a lecture, or family footage.

Step by step

Open the converter, drop your video (or several — batch works), and wait. The first use downloads the ~31 MB conversion engine, which your browser then caches; after that it's instant to start. Extraction runs at many times real-time speed for audio-only work — a one-hour lecture typically takes a couple of minutes. Then press Download, or grab everything as a ZIP if you converted a batch.

Tips for common cases

Long recordings: if you only need part of the audio, run the video through the video trimmer first (it's lossless and takes seconds), then extract MP3 from the trimmed clip. Voice memos saved as video: these convert perfectly — the black or static video track is simply discarded. Audio quality: extraction can never sound better than the source; a video with tinny 96 kbps audio produces an MP3 of that same underlying quality, because the information was never there to begin with.

A note on copyright

Extracting audio from your own recordings, lectures you have permission to use, and public-domain material is exactly what this tool is for. Ripping audio from copyrighted music videos or streaming platforms violates those platforms' terms and usually copyright law — use the official download features those services provide instead.