Opus to AAC Converter
Convert Opus to AAC free — no upload, no signup
To convert Opus to AAC, drop your Opus audio files into the box below and click Convert. Fylo converts with ffmpeg running inside your browser, so nothing is uploaded and there's no signup or watermark. Convert Opus to raw AAC.
Drop audio files here
or tap to browse · paste with Ctrl+V · add many at once
Your files never leave your device
Advanced
How to convert Opus to AAC
Add your Opus files
Drag and drop Opus files into the box or tap to choose them. The converter engine (about 31 MB) downloads once, the first time you convert.
Pick a bitrate
192 kbps suits music and 128 kbps or less suits speech. Sample rate and mono/stereo are under Advanced.
Convert and download
Click Convert, then download each AAC file or all of them as one ZIP.
Why convert Opus to AAC?
Some broadcast and streaming tools accept AAC but not Opus.
What happens when you convert Opus to AAC?
The audio is re-encoded to AAC at 160 kbps.
How does Fylo convert Opus to AAC?
Fylo decodes the Opus audio in the Opus with ffmpeg compiled to WebAssembly and encodes it with FFmpeg's AAC encoder at 160 kbps, written as a raw ADTS stream. Both formats are lossy, so each conversion discards a little detail — start from the highest-bitrate Opus you have. A 3-minute song is ≈ 2.9 MB at 128 kbps as Opus and ≈ 3.6 MB at 160 kbps as AAC. The original sample rate and channel layout are kept unless you change them under Advanced.
What's the difference between Opus and AAC?
Opus is an open, royalty-free codec standardised by the IETF as RFC 6716 in 2012. It blends speech technology from Skype's SILK with music coding from Xiph's CELT, so it handles both voice and music well. Files are usually stored in the Ogg container with the .opus extension.
AAC (Advanced Audio Coding) was standardised in 1997 as part of MPEG-2 and later MPEG-4, designed to replace MP3. It achieves better quality at the same bitrate, especially below 128 kbps. A .aac file is usually a raw ADTS stream; the same audio inside an MP4 container is called M4A.
Learn more: Opus format guide · AAC format guide
| Property | Opus | AAC |
|---|---|---|
| Compression | Lossy | Lossy |
| Typical bitrate | 24–160 kbps | 96–256 kbps |
| 3-minute song | ≈ 2.9 MB at 128 kbps | ≈ 3.6 MB at 160 kbps |
| Tags and cover art | Yes (Vorbis comments) | Limited in raw .aac (full in M4A) |
| Compatibility | Browsers, Android, WhatsApp, Discord; partial on Apple | Very wide: Apple, Android, YouTube, browsers |
| Best for | Voice notes, podcasts, streaming at low bitrates | Efficient music and video soundtracks |
| Introduced | 2012 | 1997 |
Frequently asked questions
AAC or M4A?
M4A for players and libraries.
Is quality kept?
Closely, at 160 kbps.
Is my Opus file uploaded to a server?
No. Fylo runs ffmpeg, the same engine used by professional video tools, compiled to WebAssembly inside your browser. Your Opus file is read directly from your device and never sent anywhere.
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