Step 1: Share your Opus files using the button above or by drag and drop.
Step 2: Click the 'Transform' button to start the transformation.
Step 3: Grab your converted AAC files.
Opus to AAC Transformation FAQ
What bitrate will the resulting AAC file use?
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A lossy AAC 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 AAC (WAV, FLAC) ignores the bitrate and keeps every sample.
Is converting Opus to AAC a second round of lossy compression?
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Yes, and it is worth planning around. Both formats are lossy, so the AAC 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 AAC 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. AAC is lossy but more efficient than MP3, and it handles up to 48 channels natively rather than being bolted onto a stereo design.
Will going from Opus to AAC reduce my audio quality?
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If Opus is lossy and AAC is lossless (e.g. MP3 → WAV), the AAC is no better than the Opus — you cannot recover information already discarded. If Opus is lossless and AAC is lossy, the AAC codec recompresses; at 192 kbps the result is transparent for most content.
Can I batch convert hundreds of Opus files to AAC?
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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.
Will the AAC keep the same sample rate as Opus?
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By default yes — 48 kHz Opus stays 48 kHz in AAC. If you need to downsample for compatibility (96 kHz → 44.1 kHz for CD burning), the sample-rate option applies high-quality resampling in the same encode pass.
Can I normalize loudness when converting Opus to AAC?
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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 AAC through a Normalize tool on this site.
Will my AAC play on car stereo, iPod, and Sonos?
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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. AAC sounds noticeably better than MP3 below 128 kbps and is the default audio track in MP4, YouTube, Apple Music and broadcast. AAC is patent-encumbered, and a handful of very old players still refuse it where they would accept an MP3.
Is my Opus file private during conversion to AAC?
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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 AAC 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 AAC take?
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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.
Why is the AAC louder or quieter than the Opus source?
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The converter does not change the level: it has no gain or normalize setting. If you hear a difference, your player or media library is probably applying ReplayGain or its own volume levelling on playback; switch that off to hear the AAC as it is.
