How to Extract Audio (MP3) From a Video File
Published 2026-09-01
Sometimes you only need the sound: a recorded lecture, a podcast someone filmed as a video, a voice memo mixed into a screen recording. Extracting the audio track and saving it as MP3 means a smaller file you can actually listen to on the go.
How it works under the hood
Filenary's Video to MP3 tool runs a real build of FFmpeg compiled to WebAssembly directly in your browser tab. The first conversion takes a few extra seconds while the engine loads; after that, every conversion runs fully offline on your device.
Steps
- Open the Video to MP3 tool.
- Drop in your video file (MP4, MOV, WebM, and other common formats work).
- Wait for the conversion — progress is shown as it runs.
- Download the resulting MP3.
Why browser-based FFmpeg matters
Traditional online converters upload your video to a server, process it there, and send back a download link — meaning your file (and often its content) passes through someone else's infrastructure. Because this runs as WebAssembly locally, your video is never transmitted anywhere.