Free MP4 to OPUS converter

Why convert MP4 to OPUS?

People convert MP4 to OPUS because MP4 plays nearly everywhere, but not inside every editor, browser or upload form, while Opus beats every other codec at low bitrates, which is why calls and podcasts use it.

How to convert MP4 to OPUS

1. Choose your MP4 file. Drop it on the box above, or tap to browse. You can pick several files at once.
2. Confirm the target is .opus. It is preselected when your browser can encode it; otherwise the closest available target is chosen. Adjust quality, size or the other options if you want to.
3. Convert and download. Press Convert, then Download. Your file stays on your device the whole time.

What is a .mp4 file?

MP4 carrying H.264 video and AAC audio is the one video format that plays essentially everywhere — phones, televisions, browsers, editing software and every messaging app. When something refuses to play a video, converting it to MP4 is almost always the fix.

What is a .opus file?

Opus is the codec behind nearly all modern voice and music streaming, standardised by the IETF and free to use. It stays intelligible at bitrates where other codecs collapse, and every current browser decodes it.

What to expect from this conversion

The picture track is discarded and only the sound is kept, encoded at the bitrate you choose.

Is it private?

Yes, by design. Every conversion happens inside your own browser using your device’s processor — there is no server that receives your MP4 file, so there is nothing for anyone to store, scan or leak. You can confirm it yourself: open your browser’s developer tools, watch the Network tab while you convert, and you will see no upload.

Questions about MP4 to OPUS

Is this MP4 to OPUS converter free?

Yes, completely. There is no account, no daily limit, no watermark and no premium tier.

Is my MP4 file uploaded to a server?

No. The conversion runs inside your own browser using your device's processor. The file is read from your disk, converted in memory and saved back to your disk — nothing is transmitted, so there is nothing for anyone to store.

Can I convert MP4 to OPUS online without downloading software?

Yes. This is an online MP4 to OPUS converter that runs in your browser, so there is nothing to install and no app to trust with your files. It works the same on a phone.

What happens to the quality?

The picture track is discarded and only the sound is kept, encoded at the bitrate you choose.

Can I convert several MP4 files at once?

Yes. Select as many files as you like and they are converted one after another in a single tap, with a download for each and a zip of all of them.

Can I convert MP4 to OPUS without FFmpeg or a script?

Yes — that is what this page is for. FFmpeg does the same job well if you already have it set up and thousands of files to process; for one file, or a handful, the browser is faster than installing anything.

Should I keep the original MP4 file?

Yes — keep it, converting never touches it. The reason to make a copy in another format is that MP4 plays nearly everywhere, but not inside every editor, browser or upload form.

How long does it take?

Roughly as long as the clip itself for high-definition video, because every frame is decoded and re-encoded on your own machine. Keep the tab in the foreground while it works.

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