Convert OPUS to AAC
Turn OPUS audio, including voice notes from WhatsApp, Telegram and Discord, into AAC that plays on Apple devices and almost any player. It all runs in your browser.
Why convert OPUS to AAC?
OPUS is excellent for voice and streaming, which is why messaging apps use it for voice notes, but many desktop players, editors and older devices will not open it. AAC plays natively across Apple devices and most hardware. Convert when a voice note will not open on your computer, when you want to drop a recording into an editor that rejects OPUS, or when a device only lists AAC and MP3.
Quality and file size
Both OPUS and AAC are lossy, so this is a transcode that adds a little loss on top of the OPUS encode. For voice notes and speech the difference is effectively inaudible. For music, choose 256 or 320 kbps to keep it transparent. Voice notes are often recorded at low bitrates to save data, and converting cannot add back detail that was never captured, so the AAC will sound as good as the original recording and no better.
OPUS to AAC: common questions
How do I play a WhatsApp voice note on my computer?
Voice notes are usually OPUS audio. Convert the file to AAC or MP3 here and it will open in any media player or audio editor, with nothing uploaded along the way.
Is my file uploaded anywhere?
No. The conversion runs entirely in your browser with FFmpeg compiled to WebAssembly. Your file never leaves your device, and we never see it, store it, or train on it.
Will converting OPUS to AAC reduce quality?
Only slightly, since it re-encodes lossy audio. For speech it is not noticeable. It also cannot improve a low-bitrate recording, so a voice note will sound the same as it did originally.
Should I choose AAC or M4A?
M4A for everyday use, because it wraps the same AAC audio with tags. Pick raw .aac only when a particular tool or device asks for it.
Who makes this?
We're the small team behind Xport Studio, a private, fully offline app for AI vocals, stems, and mastering. These free tools are side experiments we wanted to share. No upsell, but if you're curious about the bigger thing, take a look.