Step 1: Provide your Opus files using the button above or by toss and let go.
Step 2: Click the 'Convert' button to start the conversion.
Step 3: Fetch your converted AC3 files.
Opus to AC3 Conversion FAQ
What bitrate does the AC3 file end up at?
+
A lossy AC3 is encoded at 192 kbps by default. The Audio Quality setting also offers 320 kbps for the best quality and 128 kbps for a smaller file. A lossless AC3 (WAV, FLAC) ignores the bitrate and keeps every sample.
Is converting Opus to AC3 a second round of lossy compression?
+
Yes, and it is worth planning around. Both formats are lossy, so the AC3 encoder is working from audio that has already been through one psychoacoustic pass, and its own decisions compound the first set. At 192 kbps or above the result is still transparent for most listening. If you have a lossless master anywhere, encoding the AC3 from that instead avoids the double pass entirely. Opus scales from 6 kbps mono speech to 510 kbps stereo music in the same bitstream and switches modes automatically. AC-3 is lossy multichannel audio, normally 5.1 at 384 or 448 kbps, with metadata for dialogue normalisation and downmixing.
Will my track titles and album art survive the Opus to AC3 conversion?
+
Not intact. Opus carries a proper metadata block, but AC3 has no standard place for artist, album, track number or cover art, so tags are dropped rather than mangled. Keep the Opus as the tagged copy, or re-tag afterwards with a tool like Mp3tag or MusicBrainz Picard. AC-3 is inefficient by modern standards and is not accepted by browsers, phones or most web players without a downmix to stereo.
Will going from Opus to AC3 actually reduce my audio quality?
+
If Opus is lossy (MP3, AAC) and AC3 is lossless (WAV, FLAC), the AC3 is no better than the Opus — you cannot recover information already discarded by the lossy Opus codec. If Opus is lossless and AC3 is lossy, expect the AC3 encoder to recompress; at 192 kbps the loss is imperceptible to most ears.
Can I batch-convert hundreds of Opus files into AC3?
+
Several files in one job need a paid plan. Free use is one file per conversion, one conversion an hour. On a paid plan you can add several files to one job, then download each result on its own or all of them in one ZIP.
Can I normalize loudness in the Opus to AC3 step?
+
Not in this step. The converter has no loudness setting and leaves the level as it is. To even out the volume, run the finished AC3 through a Normalize tool on this site.
Will the AC3 play on my car stereo / iPod / Sonos / Bluetooth speaker?
+
MP3 plays almost everywhere. AAC plays on Apple devices, most Android phones and Sonos. FLAC plays on Sonos and Android but not on older iPods, and WAV plays on nearly everything but makes large files. There are no device presets on this page, so choose the target format your player supports. AC-3 is the surround track every AV receiver, DVD player and TV decodes natively, which is why it is still the broadcast baseline.
Is my Opus file private during conversion?
+
Yes. Uploaded Opus files are processed on our own conversion servers, no person reviews them, and they are never shared. The upload and the converted AC3 are both deleted automatically about 24 hours after the conversion, which leaves time to download the result. See /privacy/ for the full policy.
How long does converting a 1-hour Opus to AC3 take?
+
It depends on the size and length of the file. Small documents and images are usually ready quickly. Long videos take the longest, because most video conversions re-encode every frame.
