FSSD to CAF Converter
Processing entirely on your device — large files may take a moment.
FSSD Audio and Core Audio Format exist for different jobs: FSSD is a raw 8-bit audio dump format from early UNIX sound experiments — tiny headers, bare samples. Convert CAF files to WAV or MP3 for use outside the Apple ecosystem.
Because the whole conversion happens on your device, it is instant, unlimited and genuinely private — no accounts, no watermarks, no files on anyone's server. Multiple files are converted in one go.
How FSSD compares to CAF
| FSSD | CAF | |
|---|---|---|
| Structure | FSSD Audio container | caff header + chunk table |
| Compatibility | ffmpeg, archive tools | afconvert, Logic Pro, ffmpeg |
| Best for | Rescuing legacy audio | Apple pro-audio workflows |
How to convert FSSD to CAF
- 1
Select your files
Drag & drop your FSSD files onto the area above, or click to browse. You can add multiple files at once for batch conversion.
- 2
Convert instantly
Click "Convert to CAF". The conversion runs entirely inside your browser using WebAssembly — no upload, no queue, no waiting.
- 3
Download results
Download each converted CAF file individually, or grab everything at once as a ZIP archive.
About the FSSD format
FSSD is a raw 8-bit audio dump format from early UNIX sound experiments — tiny headers, bare samples.
ffmpeg decodes it natively inside your browser — the audio track is re-encoded to your chosen format with nothing ever uploaded.
+ Strengths
- ✓Decoded natively by ffmpeg
- ✓Runs entirely in your browser
- ✓Free, private, no watermarks
! Limitations
- −Legacy niche format
- −Modern tools rarely open it
- −Keep the original for archival round-trips
About the CAF format
CAF (Core Audio Format) is Apple's container for pro audio: 64-bit file offsets for recordings of any length, any codec as payload (PCM, ALAC, AAC), and time-stamped MIDI-style event chunks. Logic Pro exports it and macOS system sounds ship in it.
ffmpeg decodes the common PCM/ALAC payload variants, converting CAF to WAV or MP3 for use in any non-Apple DAW, player or web player.
+ Strengths
- ✓64-bit offsets — no size ceilings
- ✓Native to Logic Pro pipelines
- ✓Flexible codec payload
! Limitations
- −Apple-centric — rare outside macOS
- −Some CAF variants (UUID chunks) unsupported
- −Tag metadata Apple-specific
Why convert FSSD to CAF?
Think of it as moving your file to the container that fits the job. Legacy niche format CAF works differently: 64-bit offsets — no size ceilings If any of that sounds like your task, run the conversion — it takes seconds and nothing leaves your device.
Frequently asked questions
Is this FSSD to CAF converter really free?
Yes — completely free, with no sign-up, no watermark and no daily conversion limits. The site is supported by advertising.
Are my files uploaded to a server?
No. The conversion runs entirely inside your browser using WebAssembly, so your files never leave your device — that is what makes it instant and private.
Does it work on Windows, Mac, iPhone and Android?
Yes. Anything with a modern browser works: Windows, macOS, Linux, Android and iOS. No software installation is required.
Is there a file size limit for FSSD to CAF?
The only limit is your device's memory, since nothing is uploaded. Files up to a few hundred megabytes work fine on a modern desktop browser; very large files simply take a little longer.
Will converting FSSD to CAF reduce audio quality?
If CAF is lossless, the output contains everything the FSSD file contains — no further loss is added. If CAF is lossy, one recompression pass is unavoidable; the quality slider controls how much. Loss that already happened in the source file can never be undone by converting.
Can I convert a whole folder of FSSD files?
You can select many files at once and they are processed in a single batch. Output files land in one ZIP download when there is more than one result.