Frequently asked questions

MP4intoMP3 is a free online tool that lets you extract the audio track from any MP4 video and save it as an MP3 (or WAV/AAC/FLAC/OGG/Opus) file. Conversion happens in your browser — your files never get uploaded.

Yes, completely free with no daily limit, no signup, no premium tier, and no watermark. We display tasteful, non-intrusive ads to cover hosting costs.

No. It works in any modern browser on any device — no apps, no plug-ins, no extensions.

No. We never ask for your email or any personal information.

No. All conversion is performed locally in your browser using WebAssembly. Your files never leave your device.

You can verify in your browser developer tools (Network tab) that no file data is sent. Only the small conversion engine is downloaded once and cached.

There are no files in transit to intercept. Everything stays on your device.

We support up to 320 kbps CBR MP3 at 48 kHz — equivalent to CD quality. Lower bitrates (64–256 kbps) are also available for smaller files.

MP3, WAV (lossless PCM), AAC (M4A), OGG Vorbis, Opus, and FLAC.

MP4, MOV, MKV, WEBM, AVI, FLV, WMV, 3GP, M4V, MPEG, TS, MTS — and any audio format your video might have inside it.

When extracting an existing audio track to a lossless format like FLAC or WAV, you keep 100% of the original quality. When re-encoding to MP3 there is a small, controlled loss — choose 320 kbps for the best result.

There is no fixed limit since nothing is uploaded. The practical limit depends on your device’s available memory.

Most short videos convert in a few seconds. A 1-hour HD video may take a couple of minutes. Speed depends entirely on your device.

On first use we download the conversion engine (~25 MB). It is then cached so subsequent visits are nearly instant.

After the first load, yes — the engine is cached and you can convert files without an internet connection.

Yes. Drop in as many files as you want. They will be processed sequentially with the same settings.

Yes. Open Advanced settings to set start and end points in seconds.

Yes — boost or reduce by up to ±20 dB.

Yes, between 0.5x and 2x while preserving pitch.

Yes, including title, artist, album, year, and genre.

Yes. Enable EBU R 128 loudness normalization for podcasts and music libraries.

It is legal as long as you own the file or have permission from the copyright holder. We do not allow downloading from streaming sites — please respect copyright.

No. We do not download from YouTube or other streaming sites because that would violate their Terms of Service. You must supply your own MP4 file.