OPUS to AC3 converter
Convert OPUS to AC3 in seconds, free and unlimited. No upload, no sign-up, no watermark: your audio never leaves your device. Re-encodes the audio into AC3.
Last updated
Quick answer: To convert OPUS to AC3, add the OPUS file to the iHateFiles OPUS to AC3 converter and press Convert. The conversion runs in your browser, so the file is never uploaded, and it is free with no sign-up, watermark or size limit. Re-encodes the audio into AC3.
Should you convert OPUS to AC3?
Do this when AC3 plays somewhere OPUS does not. It is a second round of lossy compression, so set the bitrate at or above the original.
Both OPUS and AC3 are lossy
OPUS (Opus) has already discarded some of the sound, and AC3 (Dolby Digital) will discard a little more. The AC3 encoder works from the OPUS, not the original recording, so pick a bitrate at or above the source. A lower one saves space and costs quality you cannot get back.
Track details may not follow
OPUS carries artist, album and cover art tags well. AC3 has little or no room for them, so a music library that relies on tags may show the AC3 as an untitled file.
Where the AC3 will play
AC3 plays on DVD players, AV receivers and TVs.
OPUS and AC3 side by side
| OPUS | AC3 | |
|---|---|---|
| Inside the file | Opus | Dolby Digital |
| Compression | Lossy | Lossy |
| Carries sound | Yes | Yes |
| One minute of stereo | 0.25 to 1 MB | 3 to 5 MB |
| Plays on | browsers, Android, WhatsApp and Discord, but not many car stereos or older players | DVD players, AV receivers and TVs |
| Here | Read and write | Read and write |
What usually goes wrong
About the OPUS. Opus at 64 kbps sounds better than MP3 at 128, so the bitrate you are used to is roughly double what you need here.
About the AC3. Playing a 5.1 AC3 track on stereo speakers can leave dialogue almost inaudible, because the centre channel carrying it is not being mixed in. Downmixing to stereo during conversion fixes that.
How to convert OPUS to AC3
- Add your OPUS file. It is read from your disk and stays there.
- Check the settings. The output format is already set to AC3.
- Press convert and the AC3 file is saved back to your device.
Questions
How do I convert OPUS to AC3?
Open this page, add your OPUS file, and press convert. The file is decoded and re-encoded by your own browser and saved back to your device. Nothing is uploaded.
Is this OPUS to AC3 converter free?
Yes, completely. There is no account, no sign-in, no watermark and no daily limit, because there is no server doing the work. Your own device does it.
Are my files uploaded anywhere?
No. There is no upload endpoint. The conversion runs inside this browser tab, so your file never leaves your device. You can open your browser's network panel and watch: nothing carrying your file is sent.
Is there a file size limit?
No fixed limit. Because the work happens on your machine there is no server quota. The only ceiling is your own device's memory, which for video means very large files may be slow.
Will converting to AC3 lose quality?
AC3 is a lossy format, so some detail is discarded. The quality control on this page decides how much. The default is set high enough that most people cannot see the difference.
Can I convert several OPUS files at once?
Yes. Add as many as you like and they are converted one after another, then offered as a single ZIP.