MP4toMP3 converts video files you supply into audio, running locally in the browser so files are not stored on its servers. Inputs are MP4, MOV, MKV, WebM, MPEG-TS and HLS. MP3 bitrates are 128, 192 and 320 kbps, and the output selector also lists AAC, Opus, Vorbis, WAV and FLAC. It has a batch queue and an editor for trim, loop, metadata and cover art.
The site shows the badge 'Free · No signup', and no account or install is needed. It works in modern browsers on Windows, macOS, iOS and Android, and file size limits depend on your browser and device. It converts files you provide and does not download from YouTube or other platforms.
MP4toMP3 came from needing to pull audio out of lecture and podcast videos for offline listening, using a clean browser tool where you drop a video and get audio back.