S24 to ALAC Converter
Processing entirely on your device — large files may take a moment.
Convert ALAC to FLAC for non-Apple players, or MP3 for sharing. If your files are still in S24 format, this page is the shortcut: S24 is headerless 24-bit little-endian PCM — high-resolution master dumps from field recorders and audio workstations.
This converter runs entirely in your browser using WebAssembly — your files never leave your device, nothing is uploaded, and there are no watermarks, sign-ups or queues. Drop in several files at once to convert them as a batch.
How S24 compares to ALAC
| S24 | ALAC | |
|---|---|---|
| Structure | 24-bit PCM (raw) container | MP4 (alac sample entry) container |
| Compatibility | ffmpeg, archive tools | iOS, macOS, iTunes, ffmpeg |
| Best for | Rescuing legacy audio | Apple-ecosystem lossless libraries |
How to convert S24 to ALAC
- 1
Select your files
Drag & drop your S24 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 ALAC". The conversion runs entirely inside your browser using WebAssembly — no upload, no queue, no waiting.
- 3
Download results
Download each converted ALAC file individually, or grab everything at once as a ZIP archive.
About the S24 format
S24 is headerless 24-bit little-endian PCM — high-resolution master dumps from field recorders and audio workstations.
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 ALAC format
ALAC (Apple Lossless Audio Codec) is Apple's FLAC equivalent: bit-exact lossless compression inside an MP4 container, opened-source in 2011 and now native on every Apple device and most server-side pipelines. It is what iTunes Store sells as "lossless" and what iPhone recordings encode to by default.
For non-Apple players FLAC is the safer target, and conversion is sample-exact in both directions — the decode is handled by ffmpeg's native ALAC decoder without any Apple runtime.
+ Strengths
- ✓Native on every Apple device
- ✓Open source since 2011
- ✓Reasonable sizes inside MP4
! Limitations
- −Outside Apple ecosystems FLAC wins
- −Slightly worse ratios than FLAC
- −Confusing .m4a extension doubles as lossy
Why convert S24 to ALAC?
Think of it as moving your file to the container that fits the job. Legacy niche format ALAC works differently: Native on every Apple device If any of that sounds like your task, run the conversion — it takes seconds and nothing leaves your device.
Frequently asked questions
Is this S24 to ALAC 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 S24 to ALAC?
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 S24 to ALAC reduce audio quality?
If ALAC is lossless, the output contains everything the S24 file contains — no further loss is added. If ALAC 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.
Are tags like title and artist preserved?
Tag handling varies between target formats and this conversion focuses on the audio itself. For archival copies where tags matter, keep the original file; the converted copy is for playback and sharing.