AVI to OPUS Converter

AVI to Opus, or AVI to MP3?

Both conversions do the same job — decode the audio stream out of a Microsoft AVI container and throw the video away — and the only real question is which codec you write it back as. Opus wins on size and on modern-web playback; MP3 wins on being playable by absolutely everything. The short answer: choose Opus when you control what will play the file (a browser, a phone app, a self-hosted site, a chat client), and choose AVI to MP3 when the file has to work on a car stereo, an old iPod or someone else's unknown device. Files are uploaded over an encrypted connection, converted on our servers, and deleted automatically a few hours later.

Opus and MP3 Side by Side

When to Pick Opus

• Storage or bandwidth is the constraint — a spoken-word recording at 32-48 kbit/s stays clean and takes a fraction of the space of a 128 kbit/s MP3.
• The audio is destined for a website, a web app or a Progressive Web App, where Chrome, Firefox and Edge all decode it natively.
• You are feeding a modern chat or conferencing stack; Opus is the codec WebRTC standardised on, so it is what those pipelines already speak.
• You want one codec that handles both a lecture recording and a music bed without switching formats or bitrate strategies.

When to Pick MP3 Instead

• The file is going to a car head unit, a hi-fi streamer, a DAP, a gym treadmill or anything else you cannot test first.
• It is going into iTunes or Apple's Music app, which does not import .opus.
• Someone else will open it on an unspecified machine and you would rather not troubleshoot codecs.
• It is going into an older editing or podcast tool whose import list stops at MP3, WAV and AAC.

Choosing an Opus Bitrate

The File Compression group offers a Quality Preset, a fixed Constant Bitrate, a Variable Bitrate range, a Custom Bitrate you type in, or a Specific file size to hit. The Constant Bitrate dropdown opens at 128 kbit/s, which is already generous for most material.

The Variable Bitrate dropdown offers ten ranges from 6k-24k up to 320k-510k, that last one sitting at the ceiling the Opus specification defines. There is no practical reason to go near it; the codec reaches transparency for most listeners far lower than MP3 does.

How to Convert AVI to Opus

1. Upload Your AVI File: Drag your clip onto the page or click "+ Add Files" to add one or several. Everything queued converts with the same settings.
2. Set the Bitrate: Open Advanced Options and use File Compression — Constant Bitrate for a fixed rate, Variable Bitrate for a quality-targeted range, Custom Bitrate to type an exact number, or Specific file size when you have a hard limit.
3. Adjust Channels, Sample Rate and Trim (Optional): Audio Channel forces Mono or Stereo, Audio Sample Rate can downsample for speech, and Trim takes a Start time and Duration in seconds or HH:MM:SS.sss.
4. Convert and Download: Click Convert and save the .opus file. The video stream is discarded, so a large AVI still yields a small audio file.

Frequently Asked Questions

What actually plays a .opus file?

Chrome from version 33, Firefox from 15 and Edge from 14 all play Opus natively, as do VLC, mpv, foobar2000, Android and anything built on WebRTC. Safari is the awkward one: desktop Safari has only partial support even in current releases, while Safari on iOS reached full support in version 18.4. Apple's Music app will not import .opus at all. If any of that is a problem for your audience, extract to MP3 instead.

Will I lose quality converting AVI to Opus?

Some, because this is a lossy-to-lossy step in most cases. AVI usually carries MP3 or AC-3 audio, which has already been compressed once, and re-encoding to Opus sheds a little more. Opus is efficient enough that at 96-128 kbit/s the second generation is inaudible to nearly everyone. If your AVI happens to hold uncompressed PCM, you are going from lossless to lossy for the first time, so pick a higher rate.

Is Opus genuinely better than MP3 at the same bitrate?

At low and middle bitrates, generally yes — which is why WebRTC, Discord and YouTube all use it. Opus was designed to replace both Vorbis for music and Speex for speech, and it switches between a speech-oriented and a music-oriented mode internally, so it holds together at rates where MP3 audibly falls apart. Above roughly 256 kbit/s the comparison stops mattering, because both are transparent. The gap that remains is compatibility, not sound.

Why does my Opus file report 48 kHz when the AVI was 44.1 kHz?

Because Opus operates at 48 kHz internally. The encoder accepts 8, 12, 16, 24 and 48 kHz input and resamples anything else, so a CD-rate 44.1 kHz soundtrack comes out tagged 48 kHz. This is normal and not a defect — there is no audible penalty, and the file plays at the correct speed and pitch.

How high can the bitrate go?

The specification stops at 510 kbit/s for a stream, and the encoder allows roughly 256 kbit/s per channel, so a mono extraction tops out lower than a stereo one. In practice nothing above about 160 kbit/s is worth the bytes for stereo music. If you genuinely need an untouched copy of the soundtrack rather than a small one, use AVI to WAV for uncompressed PCM or AVI to FLAC for lossless compression.

Is Opus good for music, or only for voice?

Both, and that is the point of the design. Its speech layer handles dialogue and its music layer handles everything else, with the encoder switching as the material changes — so a documentary that alternates between narration and score does not need two different settings. For full songs, 96-128 kbit/s is comfortable for most listeners; push to 160-192 kbit/s for critical listening.

Can I put the Opus audio back into a video?

Not from this page, which outputs audio only. If what you actually want is a modern, small video with Opus sound, convert the AVI to WebM — that container pairs VP9 video with Opus audio and plays natively in Chrome, Firefox and Edge. Extract-then-remux is the long way round for the same result.

How do I extract only part of the soundtrack?

Use the Trim group and enter a Start time plus a Duration, in seconds or in HH:MM:SS.sss form; only that window is encoded. If you need several separate excerpts, convert once and then cut the result with the audio cutter rather than running the conversion repeatedly.

What happens to my files after conversion?

Your AVI is uploaded over an encrypted connection and converted on our servers. The upload and the finished .opus file are both deleted automatically a few hours later, there is no sign-up and no watermark, and files are never shared or made public. Since only the audio is written, the download is small even when the source video is not.