Opus → AIFF

No, and it is worth being blunt: nothing can. The Opus already discarded detail during its original encode, and wrapping what remains in a lossless AIFF preserves exactly that — no more. The file gets several times larger and sounds identical. It is still the right move before editing, because AIFF will not add a second generation of artefacts when you export. AIFF is the studio interchange format on macOS, handles metadata better than plain WAV, and imports into Logic and Pro Tools instantly. Opus is almost never supported by standalone hardware — assume software playback only, and expect car stereos to ignore it.

If Opus is lossy and AIFF is lossless (e.g. MP3 → WAV), the AIFF is no better than the Opus — you cannot recover information already discarded. If Opus is lossless and AIFF is lossy, the AIFF codec recompresses; at 192 kbps the result is transparent for most content.

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.

By default yes — 48 kHz Opus stays 48 kHz in AIFF. 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.

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 AIFF through a Normalize tool on this site.

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. AIFF is as large as WAV with worse support outside the Apple world, so it is a poor choice for distribution.

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 AIFF are both deleted automatically about 24 hours after the conversion, which leaves time to download the result. See /privacy/ for the full policy.

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.

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 AIFF as it is.