Free Video to MP3 — extract audio without uploading
Drop in an MP4, WebM, MOV, MKV, AVI, FLV, 3GP or WMV file and pull the soundtrack out as MP3, WAV, OGG, M4A, AAC or FLAC. Bitrate up to 320 kbps, optional trim. The whole conversion runs in your browser via FFmpeg.wasm — your video never leaves your device.
First run downloads ~25 MB of FFmpeg.wasm (cached afterwards). After that, audio extraction takes seconds.
Why people pull audio out of video
"MP4 to MP3" hits ~4M searches a month. The reasons are surprisingly varied.
Podcast prep
Strip the video stream from a Zoom or interview recording before editing in Audacity / Audition.
Music ripping
Lift a backing track or live-set audio out of a personal video for offline listening.
Lecture notes
Turn a recorded class into a phone-friendly MP3 to revise on a commute or run.
Voice memo extract
Pull voice from a screen-recorded walkthrough so it can be re-used in a tutorial.
Transcription prep
Most cloud transcription services charge by audio length and prefer MP3 / WAV inputs over MP4.
Storage saving
Audio-only of a 4K video is typically 5–10% of the original size — handy for archival.
FFmpeg, but running in your tab
Pick a video
Drop the file or click to browse. The browser previews it via a blob URL — nothing is uploaded.
Load the engine
The first time you click Extract, the page downloads ~25 MB of FFmpeg.wasm from jsDelivr. After that it's cached and starts instantly.
Run the conversion
FFmpeg runs the equivalent of ffmpeg -i video -vn -acodec libmp3lame -b:a 192k output.mp3 inside this tab. Progress is reported live.
Preview & download
The output is wrapped in a Blob, dropped into an <audio> element, and saved with a one-click download. Source video is discarded from memory.
Frequently asked questions
No. The video is decoded by FFmpeg compiled to WebAssembly, running entirely inside this browser tab. Your file never leaves your device. Network requests are only made on first run to download the FFmpeg.wasm core from jsDelivr.
Inputs: MP4, WebM, MOV, MKV, AVI, FLV, 3GP, WMV, OGV — anything FFmpeg understands. Outputs: MP3, WAV, OGG (Vorbis), M4A (AAC), AAC, FLAC.
The first run downloads ~25 MB of FFmpeg.wasm core (cached afterwards by your browser). After that, conversion runs at roughly real-time on a desktop CPU — 5 minutes of audio takes 5–10 seconds on most machines. Mobile is slower (2–4× real-time).
Soft cap around 2 GB on desktop and ~500 MB on mobile due to browser memory limits. Files above that may freeze the tab — trim a section first or use a desktop browser.
128 kbps is the YouTube standard, transparent for spoken-word audio. 192 kbps is the sweet spot for music. 320 kbps is the lossy ceiling — only meaningful if the source is also high quality. Pick WAV or FLAC for lossless.
Yes. Enter start and end times in the Trim fields (formats accepted: 1:23, 1:23.5, 83 seconds, 1:02:30). Or scrub the video to a position and click "Set end" to grab the current playhead. Leave both empty for the full audio track.
About browser-side video conversion
For over a decade, "MP4 to MP3" meant either installing a desktop tool (Audacity, VLC, HandBrake) or uploading your file to a web service that charged for the privilege. Neither is great — desktop tools have a learning curve, and uploading personal audio to someone else's server is a poor privacy trade. FFmpeg.wasm changed that.
What FFmpeg.wasm is
FFmpeg is the codec swiss-army-knife that powers VLC, YouTube, Netflix, Chrome's built-in player, and virtually every other video stack on the planet. FFmpeg.wasm is the same C codebase compiled to WebAssembly, which means it runs at roughly native speed inside a browser tab with no installation. The page you're looking at is a thin UI wrapper around the exact same library.
Why it stays on your machine
- The input file is read with
FileReader/arrayBuffer()and written straight into FFmpeg's in-memory filesystem (MEMFS). It never travels over the network. - The output is read back from MEMFS as bytes, wrapped in a
Blob, and either played from ablob:URL or saved via a generated anchor. - The only network call on this page is the one-time fetch of the FFmpeg core (from jsDelivr) — and that's cached for every subsequent run.
Format quick-pick
- MP3 — universal compatibility, lossy. The right default unless you have a reason to pick something else.
- WAV — uncompressed PCM. Best for editing, biggest file (~10 MB per minute of stereo CD-quality audio).
- OGG (Vorbis) — open-source, slightly better than MP3 at the same bitrate, less universally supported.
- M4A / AAC — what iTunes / Apple Music uses. Slightly better than MP3 at low bitrates.
- FLAC — lossless and ~50% smaller than WAV. Best for archival.
Performance notes
This page uses the single-threaded FFmpeg.wasm build (it doesn't require SharedArrayBuffer, which needs special headers most sites don't set). On a modern laptop you'll see roughly 30× real-time for MP3 encoding — a 10-minute video gives an MP3 in ~20 seconds. The multi-threaded build is 2–3× faster but requires the page to be served with COOP/COEP isolation, which we deliberately avoid here for compatibility.