Convert MP4 to MP3 without uploading

Why no upload matters

How it works

When you choose a video, it is opened directly from your device's storage. Only the audio track is read; the picture is skipped. Your browser decodes the audio with its built-in decoder (WebCodecs), and the LAME MP3 encoder, running inside the page as WebAssembly, turns it into an MP3. Nothing is sent anywhere, which is why it is fast, private and works offline.

MP3 320, 192 or 128 kbps re-encodes the audio as MP3, the format every phone, car and player understands. Original audio copies the audio track out of the video exactly as it is, without re-encoding: it is lossless, and because most videos store their audio as AAC, you usually get an M4A file.

Made for lectures, music, voice notes and iPhone videos

Lectures, meetings and podcasts

Recorded a class, a Zoom call or a podcast as video? Save just the sound as an MP3 that is a fraction of the size, to listen on the go or to send to a transcription tool. 128 kbps is plenty for speech.

Music and live recordings

Keep the audio of a concert clip or a song you recorded as an MP3 at 320 kbps, or pick Original audio to keep it exactly as recorded.

iPhone and Android videos (MOV to MP3)

iPhone videos are MOV files. Choose them straight from your photo library and get an MP3, or an M4A with the original sound, without installing an app.

Private recordings

Interviews, voice memos filmed on a phone, family videos: because nothing is uploaded, no one else ever hears them.

Frequently asked questions

Is my video uploaded anywhere?

No. MP4toMP3 never uploads your video. The file is read inside your browser on your own phone or computer, the audio is extracted and encoded there, and the MP3 is saved straight back to your device. No server ever receives it.

How do I convert MP4 to MP3?

Pick a quality (192 kbps is right for most uses), then choose or drop your MP4 files. Conversion starts right away on your device, and each MP3 can be downloaded on its own or all together as a ZIP.

Which bitrate should I choose: 128, 192 or 320 kbps?

192 kbps sounds the same as the original for most people and is the default. 320 kbps is the highest MP3 quality, useful for music you want to keep. 128 kbps makes the smallest files and is fine for speech such as lectures and podcasts. A higher bitrate can't add quality the video's audio doesn't have, so the app tells you when the source is lower than what you picked.

Can I extract the audio without any quality loss?

Yes. Choose Original audio. Instead of re-encoding, the app copies the audio track out of the video exactly as it is: AAC audio becomes an M4A file, and MP3, Opus, Vorbis, FLAC or PCM audio is saved in a matching format. It is lossless and very fast. MP3 is always a re-encode, because most videos store their audio as AAC, not MP3.

Does it work offline?

Yes. After your first visit the whole app is stored in your browser, so you can open it and convert videos to MP3 without an internet connection. You can also install it to your home screen or desktop like an app.

Which formats and sizes are supported?

MP4, MOV (including iPhone videos), M4V, WebM, MKV and MPEG-TS videos, plus audio files such as M4A, WAV, FLAC and OGG, up to 2 GB each and up to 50 files at a time.

Can I convert many videos to MP3 at once?

Yes. Select or drop up to 50 files. They are converted one after another, and you can download each MP3 separately or all of them as a single ZIP file.

Does it work on iPhone and Android?

Yes, in a recent version of Safari on iPhone and Chrome on Android. Choose a video from your gallery or files and the MP3 is saved to your downloads.

Is it free? Do I need an account?

It is free, with no account, no watermark, no sign-up and no daily limit.