ALAC to GSM Converter
Processing entirely on your device — large files may take a moment.
Apple Lossless and GSM 06.10 Speech exist for different jobs: ALAC is Apple's lossless codec inside an MP4 container — the iTunes Store lossless tier and every big iOS recording. Convert GSM speech recordings to WAV or MP3.
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 ALAC compares to GSM
| ALAC | GSM | |
|---|---|---|
| Structure | MP4 (alac sample entry) container | Raw GSM frames (33 bytes/20ms) |
| Types / schema | Lossless, 16-32-bit | Lossy speech codec (RPE-LTP) |
| Compatibility | iOS, macOS, iTunes, ffmpeg | Asterisk, SoX, ffmpeg |
| Best for | Apple-ecosystem lossless libraries | Telephony recordings |
How to convert ALAC to GSM
- 1
Select your files
Drag & drop your ALAC 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 GSM". The conversion runs entirely inside your browser using WebAssembly — no upload, no queue, no waiting.
- 3
Download results
Download each converted GSM file individually, or grab everything at once as a ZIP archive.
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
About the GSM format
GSM 06.10 is the speech codec of the original GSM mobile network — 13 kbit/s RPE-LTP that made digital cellphone calls possible in 1991 and still lives inside VoIP systems, old answering machines and Asterisk PBX recordings.
It is lossy speech, not music: converting GSM to WAV or MP3 preserves intelligibility perfectly while finally letting desktop players open the file without special codecs.
+ Strengths
- ✓Tiny bitrate for speech intelligibility
- ✓Ubiquitous in telephony systems
- ✓Decodes natively via ffmpeg
! Limitations
- −Speech-only quality — music falls apart
- −13 kbit/s artifacts are audible
- −8000 Hz sample rate only
Why convert ALAC to GSM?
Converting makes sense where the strengths of GSM meet what ALAC cannot give you. Tiny bitrate for speech intelligibility Meanwhile Outside Apple ecosystems FLAC wins One pass through the converter above puts your file on the right side of that trade-off.
Frequently asked questions
Is this ALAC to GSM 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 ALAC to GSM?
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.
Can I convert a whole folder of ALAC 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.
Will converting ALAC to GSM reduce audio quality?
If GSM is lossless, the output contains everything the ALAC file contains — no further loss is added. If GSM 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.