Convert CAF to WMA — Free Online Tool
Convert CAF audio files to WMA format using FFmpeg.wasm entirely in your browser — no uploads required. This conversion transcodes Apple's Core Audio Format (typically PCM or AAC audio) into Microsoft's WMA container using the wmav2 codec, making your audio files compatible with Windows Media Player and Windows-centric workflows.
to
FFmpeg Command
Copy this command to run the same conversion locally with FFmpeg on your desktop. Download FFmpeg
Drop your CAF file here
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Free — no uploads, no signups. Your files never leave your browser.
Settings
Note: Browser-based encoding uses approximate quality targets. For precise CRF compression, copy the FFmpeg command above and run it on your desktop.
Estimated output:
Conversion Complete!
DownloadHow It Works
CAF files commonly store uncompressed PCM audio (such as pcm_s16le, the default) or compressed audio like AAC or FLAC inside Apple's container. During conversion, FFmpeg decodes whatever audio codec is present inside the CAF container and re-encodes it as WMA using the wmav2 codec at the target bitrate (128k by default). This is a full transcode — not a remux — because CAF and WMA share no compatible audio codecs. If your source CAF contains lossless PCM or FLAC audio, be aware that encoding to WMA introduces lossy compression for the first time; if your CAF already contains AAC, this conversion is a lossy-to-lossy transcode, which can compound quality loss.
What Each Flag Does
| Flag | What it does |
|---|---|
ffmpeg
|
Invokes the FFmpeg multimedia processing engine. In this browser-based tool, it runs as FFmpeg.wasm compiled to WebAssembly, so no files leave your device. |
-i input.caf
|
Specifies the input file as a CAF (Core Audio Format) file. FFmpeg will detect and decode whatever audio codec is stored inside the CAF container — commonly pcm_s16le for uncompressed audio, or AAC for compressed Apple audio. |
-c:a wmav2
|
Sets the audio encoder to wmav2, Microsoft's second-generation Windows Media Audio codec. This is the standard and most efficient codec for WMA files, offering better quality-per-bit than the older wmav1 and broad compatibility with Windows Media Player and other WMA-supporting software. |
-b:a 128k
|
Sets the audio bitrate to 128 kilobits per second for the wmav2 encoder. This is a reasonable default for general-purpose stereo audio; increase to 192k or 256k for music where fidelity matters, or reduce to 96k for speech-only content to save file size. |
output.wma
|
Defines the output filename and tells FFmpeg to write the result as a WMA file inside an ASF container. The .wma extension is recognized natively by Windows and Windows Media Player without any additional codecs. |
Common Use Cases
- Preparing Apple-recorded audio (from GarageBand, Logic Pro, or Core Audio APIs) for distribution on Windows platforms that expect WMA files
- Converting CAF voiceover recordings from iOS or macOS apps into WMA for use in Windows-based video editing or e-learning authoring tools like Articulate Storyline
- Migrating a CAF-based audio library to WMA for compatibility with legacy Windows Media Player or Zune software on older Windows systems
- Delivering WMA audio files required by enterprise content management systems or digital asset platforms that do not accept Apple-proprietary CAF containers
- Transcoding high-resolution CAF recordings (e.g., 24-bit PCM from professional recording setups) into WMA for streaming scenarios where CAF is not a supported input format
Frequently Asked Questions
Yes. If your CAF file contains uncompressed PCM audio (the CAF default codec, pcm_s16le), converting to WMA with wmav2 at 128k introduces lossy compression for the first time. WMA is inherently a lossy format, so some audio detail will be discarded during encoding. To minimize quality loss, choose a higher bitrate like 256k or 320k when doing this conversion.
Yes, this is a lossy-to-lossy transcode. FFmpeg will decode the AAC audio from the CAF container and re-encode it as wmav2, which means two rounds of lossy compression are applied. Each generation of lossy encoding removes additional audio information, and the result will be audibly worse than the original AAC source. If audio fidelity is critical, consider keeping the AAC stream in a more universally compatible container like M4A or MP4 instead.
Partially. WMA supports metadata through ASF (Advanced Systems Format) tags such as title, artist, and album, and FFmpeg will attempt to map standard CAF metadata fields to their WMA equivalents during conversion. However, CAF-specific or non-standard metadata fields may be dropped. It is worth inspecting the output WMA file in a tag editor like Mp3tag to confirm which tags transferred correctly.
Replace the value after '-b:a' in the command. For example, to encode at 256k instead of the default 128k, use: ffmpeg -i input.caf -c:a wmav2 -b:a 256k output.wma. The WMA format supports bitrates from 64k up to 320k — higher values produce better audio quality at the cost of a larger file size. For speech content, 96k is usually sufficient; for music, 192k or higher is recommended.
Yes, by replacing '-c:a wmav2' with '-c:a wmav1' in the command: ffmpeg -i input.caf -c:a wmav1 -b:a 128k output.wma. WMA v1 is an older codec with lower efficiency, meaning it achieves worse audio quality at the same bitrate compared to wmav2. You should only use wmav1 if you need compatibility with very old Windows Media Player versions or legacy hardware that cannot handle the wmav2 codec.
The single-file command shown on this page handles one file at a time, but you can run a batch conversion locally using a shell loop. On Linux or macOS: for f in *.caf; do ffmpeg -i "$f" -c:a wmav2 -b:a 128k "${f%.caf}.wma"; done. On Windows Command Prompt: for %f in (*.caf) do ffmpeg -i "%f" -c:a wmav2 -b:a 128k "%~nf.wma". The browser-based tool processes files individually, so for bulk conversions the local FFmpeg approach is more practical.
Technical Notes
CAF (Core Audio Format) is Apple's flexible audio container, capable of holding a wide range of codecs including uncompressed PCM (in various bit depths), AAC, FLAC, Opus, Vorbis, and G.711 variants (alaw/mulaw). It was designed to remove the 4GB file size cap present in AIFF and WAV, making it suitable for long professional recordings. WMA, by contrast, is built on Microsoft's ASF container and is restricted to lossy wmav2 or wmav1 audio codecs — there is no lossless WMA variant accessible via standard FFmpeg encoding (WMA Lossless, wmav_lossless, exists but has limited support). Because no codec is shared between CAF and WMA, every conversion requires a full decode-and-reencode cycle. File sizes after conversion depend heavily on the source: a large uncompressed PCM CAF file will shrink dramatically when encoded to WMA at 128k, while a highly compressed AAC CAF at low bitrate may actually produce a similar-sized or slightly larger WMA file. WMA's DRM support is a container-level feature and is not applied by FFmpeg; the output WMA files from this tool are DRM-free. Note also that WMA files are not natively playable on macOS or iOS without third-party software, so this conversion is specifically suited for Windows-targeted delivery.