OPUS to M4A converter
Convert Opus to M4A free online. Re-encode Opus audio into AAC for Apple devices, iTunes, and players that lack Opus support. No signup, 500 MB limit.
Drop a file to convert here
or click to browse
About MPEG-4 Audio
Common Use Cases
- Playing Opus audio on Apple devices
- Converting voice recordings from messaging apps
- Migrating Opus downloads to Apple-friendly format
Opus is a modern, open-source lossy codec that excels at both voice and music, especially at low bitrates. It is the default audio format for WebRTC, Discord, Telegram, and many voice recording apps. The catch is that Apple devices and iTunes do not support Opus playback. M4A (AAC) is Apple's native format and plays everywhere in the Apple ecosystem. Converting Opus to M4A lets you listen to your Opus audio on any Apple device.
Both Opus and AAC (inside M4A) are lossy codecs. Opus generally performs better at low bitrates (under 128 kbps), while AAC matches or beats it at higher bitrates. The main difference for this conversion is compatibility: M4A plays on Apple devices, Opus does not.
Why Convert Opus to M4A?
Apple ecosystem support
iPhones, iPads, Apple TV, HomePods, and Apple Watch all play M4A natively. Opus support on Apple devices does not exist outside of web browsers, and even Safari added it only recently.
Voice recording migration
Telegram, Discord, and many voice recording apps save audio as Opus. If you export voice messages or recordings and want to play them on Apple devices, M4A is the target format.
iTunes and Apple Music library
M4A imports into iTunes and Apple Music with full metadata support. Opus files cannot be added to iTunes at all.
Broader player compatibility
Beyond Apple, M4A plays on virtually all Android devices, car stereos, smart speakers, and media players. Opus support, while growing, is still missing from many devices.
When to use each
Keep Opus when...
- Streaming where bandwidth is limited
- VoIP and real-time communication
- Web audio in supported browsers
- The playback chain supports Opus
- File size at low bitrate is critical
Convert to M4A when...
- Playing on Apple devices
- Adding to iTunes or Apple Music
- Listening in the car via CarPlay
- Sharing via AirDrop or iMessage
- Building a device-agnostic music library
Common use cases
- Playing Opus audio on Apple devices
- Converting voice recordings from messaging apps
- Migrating Opus downloads to Apple-friendly format
How to use
- Upload your Opus file. Drag and drop an .opus file onto the upload area, or click to browse from your device. Files up to 500 MB are supported.
- Start the conversion. Click Convert File. Your Opus audio is decoded and re-encoded as AAC inside an M4A container on our servers using FFmpeg.
- Download your M4A. Once processing finishes, click the download link to save your M4A. Both the uploaded Opus and converted output are deleted from our servers within 1 hour.
Frequently asked questions
- Does converting Opus to M4A lose quality?
- Yes, slightly. Both are lossy formats, so transcoding introduces a small generational loss. At higher bitrates (128 kbps+), the difference is negligible on consumer playback systems.
- Can I convert Telegram or Discord voice messages?
- Yes. Both apps use Opus for voice messages. Export the .opus file from the app and upload it here to get an M4A that plays on any device.
- Why does Apple not support Opus?
- Apple has historically backed AAC as its preferred codec. Safari added Opus support in iOS 17 for web playback, but system-level Opus support for local files and apps still does not exist.
- Will the file be larger or smaller?
- At the same perceived quality, M4A (AAC) files are usually slightly larger than Opus files because Opus achieves better compression at low bitrates. The difference is small at higher bitrates.
- Is converting Opus to M4A free?
- Yes. Anyone can convert for free with no signup. Anonymous users have a daily cap, registered accounts get higher limits, and Premium or Lifetime members get unlimited conversions.
- Does metadata transfer from Opus to M4A?
- Yes. FFmpeg reads Opus/Ogg metadata tags and maps them to M4A metadata fields. Title, artist, and album information is preserved when present in the source file.
- Is there a file size limit?
- Yes. The maximum upload size is 500 MB.