Free online CAFF to AC3 converter

Source format

CAFF stands for Core Audio Format, an Apple audio container format used mainly on macOS and iOS. It can store uncompressed or compressed audio, along with metadata such as markers and loop points. CAFF is most often encountered in Apple workflows, audio production tools, and some game or multimedia assets where high-quality audio storage is needed.

Target format

AC3 is Dolby Digital Audio, a compressed surround-sound audio format widely used in DVDs, broadcast media, home theater systems, and video files. Its main advantages are broad playback support in video ecosystems, efficient compression, and compatibility with multichannel audio. AC3 is typically used when audio needs to be embedded in video or delivered in a format recognized by consumer AV devices.

How to perform the conversion

The most reliable way to convert .caff to .ac3 is with FFmpeg, which supports both formats and gives you control over channels, bitrate, and sample rate.

1. Install FFmpeg on your computer.
2. Open a terminal or command prompt in the folder containing the CAFF file.
3. Run a conversion command such as ffmpeg -i input.caff -c:a ac3 -b:a 448k output.ac3.
4. If you need a different bitrate, adjust -b:a to match your target quality and compatibility needs.
5. Check the resulting file in a media player or with ffprobe output.ac3 to confirm the codec and audio properties.

If you prefer a simpler workflow, you can convert the file on 101convert.com for free without installing any software.

In some cases, Audacity or Adobe Audition can open CAFF files for editing, but they usually export to intermediate formats first; for direct CAFF to AC3 conversion, FFmpeg is the best choice.

Notes on quality and compatibility

CAFF is often uncompressed or lightly compressed, so the source audio may be very high quality. Converting to AC3 is a lossy process, so some audio detail will be discarded during encoding. For best results, start from the highest-quality CAFF source available.

AC3 is commonly limited to specific channel layouts and bitrates depending on the playback target. Stereo and 5.1 surround are the most common use cases. If your CAFF file contains unusual sample rates, multiple channels, or metadata, some of that information may not carry over to AC3.

Because AC3 is primarily a delivery format for video and home theater, it is not ideal for archival storage or further editing. If you need to preserve the original audio for future work, keep the CAFF file as a master copy and use AC3 only for distribution.