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MP4 to MP3.

Convert MP4 to MP3 and keep only the sound.

→ Open the extractorFree, no account, and your video is never uploaded

How it works.

Save just the sound, as an MP3, M4A, or WAV.

  1. Step 1

    Drag your video in

    Or click to choose a file. It stays on your device.

  2. Step 2

    Pick a format, or a range

    MP3 at 128, 192, or 320 kbps.

  3. Step 3

    Save the audio

    One MP3 file, straight to your device.

In detail

An MP4 is a box with a picture and a soundtrack in it. If all you want is the soundtrack, there is no reason to carry the rest: this reads the audio track out of the MP4 and writes an MP3 at 128, 192, or 320 kbps. The video is discarded before a single frame is decoded, which is why an hour-long file takes seconds rather than minutes. It runs in your browser and nothing is uploaded.

What it gives you.

  • MP3 at 128 to 320 kbps

    The number people mean when they say quality. 192 kbps is the default because it is clean on speech and music both, and 320 is there when the source deserves it.

  • Lossless WAV

    16-bit PCM, every sample the decoder produced. It runs about 11 MB a minute in stereo, which is the price of losing nothing.

  • M4A, usually as a straight copy

    Most video already carries AAC audio, and M4A is AAC in the container Apple's apps expect. When that is your source the audio is copied, not re-encoded.

  • A file built for transcription

    Mono Opus at 32 kbps turns a 500 MB video into a few megabytes, which is the smallest thing speech recognition can still hear properly.

  • Trim a range first

    Two marks on the waveform and only that section is extracted. The in and out timecodes end up in the filename so you can tell two clips apart.

  • Runs in your browser

    The file never leaves your machine. No upload, no queue, no watermark, and no stranger holding your recording.

Straight answers.

Can I convert an MP4 to an MP3 without uploading it anywhere?

Yes, and that is the whole point of doing it here. Your browser can decode the audio track and encode an MP3 on its own, so the file stays on your machine. A converter site that asks you to upload first is moving a gigabyte across the internet to do work your laptop can do locally.

Does extracting audio lose quality?

It depends what you ask for. If the video already carries the codec you want, AAC into an M4A or MP3 into an MP3, the packets are copied byte for byte and nothing is lost. WAV is lossless from the moment the track is decoded. MP3 is a re-encode, so it is a second generation, which at 192 kbps or higher is not something you will hear on speech.

MP3, M4A, or WAV: which one?

MP3 if it has to play everywhere, including a car stereo from 2006. M4A if the audio in your video is already AAC, because then it is a copy rather than a re-encode and it is both faster and cleaner. WAV if it is going into an editor or a mastering chain and the file size does not matter.

How do I send audio to a transcription tool?

Pick For transcription. It writes mono Opus at 32 kbps, which is what speech recognition services actually want: one channel, a low bitrate, and no picture at all. An hour of talking comes out around 14 MB instead of several gigabytes, so the upload is a moment rather than an afternoon.

Will it open my MOV, MKV, or WebM?

Yes. MP4, MOV, MKV, WebM, MP3, M4A, WAV, FLAC, and Ogg are all read by the browser directly. AVI and a few other old containers go through a WebAssembly build of ffmpeg that loads on demand, and so does surround audio like AC3 that browsers cannot decode. The tool says which of those is about to happen before it starts.

How big will the audio file be?

The plan line tells you before you commit. MP3 at 192 kbps is about 1.4 MB a minute, so an hour is roughly 86 MB. Mono Opus at 32 kbps is about 240 KB a minute. Stereo WAV at 48 kHz is 11.5 MB a minute, which is why a two-hour lecture in WAV is over a gigabyte and why the transcription preset exists.

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