Skip to main content
FormatDrop
Home›Audio›OPUS to AAC
OPUS
→
AAC

Opus to AAC Converter — Free, Online, No Upload

AAC opens doors that Opus can't — convert for broadcast delivery, Apple devices, and streaming platform requirements.

Free · no signup2 free files a day100% in-browser · no upload

Tap to select OPUS files

or click to browse

2 free files per day (2 left today) · Up to 10 MB each · Upgrade for more

✓ Files never uploaded✓ 100% browser-based✓ No account required
Need the reverse?AAC → OPUS

How to convert OPUS to AAC online

  1. 1

    Drop your OPUS file

    Drag your Opus Interactive Audio Codec file onto the box above, or click it to pick a file.

  2. 2

    Wait a few seconds

    Conversion starts on its own and runs on your device, not on a server.

  3. 3

    Download your AAC

    Click Download to save the Advanced Audio Coding file.

OPUS vs AAC: format overview

OPUS

Opus Interactive Audio Codec

IETF / Xiph.Org · 2012

Compression
lossy
Transparency
No
  • ✓ Best low-bitrate quality of any audio codec
  • ✓ Royalty-free and open standard (RFC 6716)
  • ✗ Not supported on iOS/macOS natively
AAC

Advanced Audio Coding

Dolby, Fraunhofer, Sony, Nokia · 1997

Compression
lossy
Transparency
No
  • ✓ Successor to MP3 — better quality at same bitrate
  • ✓ Native support across Apple, Android, YouTube

OPUS magic bytes: 4F 67 67 53 (Ogg container)

AAC magic bytes: FF F1 (ADTS) / 00 00 00 xx 66 74 79 70

Why convert OPUS to AAC?

Opus has excellent browser and streaming platform support, but commercial distribution pipelines — broadcast delivery, podcast hosting platforms, Apple devices, and streaming upload portals — are built around AAC and MP3 as the accepted input formats. Apple Podcasts Connect accepts AAC/M4A. Spotify's upload portal takes MP3 or AAC. YouTube processes MP3, AAC, WAV, or FLAC. If you're taking Opus audio from a WebRTC recording, a Discord export, or a streaming pipeline and need to submit it somewhere for commercial distribution, AAC is almost always the correct output format.

AAC is also what Apple devices require for native playback. iPhone, iPad, Apple TV, HomePod, and CarPlay are all built around AAC as the primary compressed audio codec. Smart TVs running Android TV, Tizen, or webOS support AAC universally. Broadcast standards for digital radio (DAB+) and streaming (HLS) use AAC as the codec. Converting Opus to AAC opens up essentially every distribution channel that Opus is closed out of.

Both Opus and AAC are lossy codecs, so transcoding between them causes a small quality reduction. The 192 kbps AAC this converter writes keeps that small for music. For voice-only content, 128 kbps AAC sounds excellent. The file will be slightly larger than the Opus source at equivalent perceived quality because AAC is less efficient than Opus, particularly at lower bitrates.

Quality & file size: OPUS to AAC

Typical sizes (3-minute song): OPUS 1–3 MB → AAC 2–5 MB.

AAC output is encoded at 192 kbps.

Re-encoding one lossy format into another adds a second round of compression.

Frequently asked questions

Is there a quality difference between Opus and AAC at similar bitrates?
At low bitrates (below 96 kbps), Opus is superior. Above 128 kbps, the difference is negligible in listening tests. This converter writes the AAC at 192 kbps to keep that generation loss small.
What streaming platforms require AAC instead of Opus?
Apple Podcasts, Spotify (for uploads), YouTube, and most broadcast delivery platforms require MP3 or AAC/M4A. Opus is used internally by some platforms for delivery but is rarely accepted as an upload format.

Your OPUS file never leaves this tab — FormatDrop has no endpoint that receives file data. How it works