Video to Audio (MP4 to MP3)

About this tool

This free tool extracts the audio track from a video and saves it as an audio file — the classic MP4 to MP3 conversion, plus M4A and WAV output. It's perfect for pulling the sound out of a recording, lecture, interview or music video.

Everything runs 100% in your browser using WebAssembly (ffmpeg). Your video is never uploaded to a server — the conversion happens on your own device, so it's private and there's no file-size limit imposed by an upload.

The audio engine (about 30 MB) downloads once the first time you use the tool, then is cached by your browser. After that, extraction works even offline. Because the work runs in a background worker, you can switch to another tab while it finishes — just keep this one open.

Features

• MP4 to MP3 — plus WebM, MOV and MKV input
• Three output formats — MP3, M4A (AAC) or WAV (lossless)
• Choose the quality — 128, 192, 256 or 320 kbps
• Private — your file never leaves your device
• No upload, no sign-up, no watermark

How to use it

• Upload a video — click the box or drag a file in (MP4, WebM, MOV or MKV)
• Pick a format — MP3 for the widest compatibility, M4A for smaller files, WAV for lossless
• Choose the quality — a higher bitrate sounds better but makes a larger file
• Click "Extract audio" — the first run downloads the engine; you can switch tabs while it works
• Play and download the audio when it's ready

Frequently asked questions

Is it really free with no watermark?

Yes — it's completely free, adds no watermark, and there's no sign-up.

Are my files uploaded anywhere?

No. The conversion runs in your browser on your device; the video is never sent to a server.

Which is best, MP3 or M4A?

MP3 plays almost everywhere. M4A (AAC) gives slightly better sound at the same size, and WAV is uncompressed (largest file, no quality loss).