Audio Format
What Is ALAC?
ALAC (Apple Lossless Audio Codec) is Apple's lossless compression format. Like FLAC, it stores audio without removing any data — the decoded output is bit-for-bit identical to the original. ALAC is natively supported on iPhones, iPads, Macs, iTunes, and Apple Music.
Key facts
- Type
- Lossless compressed
- File extensions
- .alac, .m4a (when in MPEG-4 container)
- Developed by
- Apple (open sourced in 2011)
- Typical file size
- ~20–40 MB per 3-min track
- Compression
- ~40–60% smaller than WAV/AIFF
- Max bit depth
- 32-bit
How it works
ALAC compresses audio data using a lossless algorithm — similar in principle to FLAC, though developed independently by Apple. When you decode an ALAC file, the output is bit-for-bit identical to the original PCM recording. Nothing is permanently removed during compression.
ALAC files are commonly stored with a .m4a extension (inside an MPEG-4 container) or with a standalone .alac extension. If you open a .m4a file and the codec shows as "Apple Lossless" or "ALAC", the audio is lossless. If it shows "AAC", the audio is lossy.
ALAC vs FLAC
Both are lossless compression formats with essentially identical audio quality. The practical difference is ecosystem compatibility:
- —ALAC plays natively on iPhone, iPad, Mac, iTunes, and Apple Music. Less support on Android and non-Apple platforms without third-party apps.
- —FLAC plays natively on Android, Linux, VLC, and most PC-based music players. Not natively supported on iOS or iTunes.
Neither is objectively better — the right choice depends on your devices. Converting between them involves no quality loss.
Common uses
- —Lossless music libraries on Apple devices via iTunes or Apple Music
- —Hi-fi listening on iPhone or iPad with high-quality headphones
- —Archiving recordings in lossless quality within the Apple ecosystem
- —Apple Music's "Lossless Audio" feature streams in ALAC
Strengths
- +Lossless — perfect reproduction of the original audio
- +40–60% smaller than WAV or AIFF
- +Native support on all Apple devices, iTunes, and Apple Music
- +Open sourced by Apple — supported in VLC, ffmpeg, and other tools
Weaknesses
- −Not natively supported on Android without third-party apps
- −Less compatible with non-Apple hardware (car stereos, hi-fi players)
- −Still much larger than MP3 — not practical for sharing or streaming
- −Files with .m4a extension may be confused with AAC-encoded M4A files
When to convert ALAC
- —Convert to MP3 for sharing, streaming, or playback on any device
- —Convert to FLAC for lossless quality with broader non-Apple platform support
- —Convert to WAV for use in DAWs and editing software that do not handle ALAC
Frequently asked questions
Is ALAC the same quality as FLAC?
Yes. Both are lossless — the decoded audio from either format is identical to the original PCM source. ALAC is Apple's implementation; FLAC is open source. The audio quality is exactly the same.
How do I know if my .m4a file is ALAC or AAC?
Check the file info in iTunes/Music — it will say "Apple Lossless" or "AAC" under the codec or format field. You can also inspect with VLC (Media > Codec Information) or a tool like MediaInfo. If it's AAC, the audio is lossy; if it's Apple Lossless, it's lossless.
Can I play ALAC on Android?
Not natively. Android does not support ALAC without a third-party app. If you want lossless audio on Android, convert to FLAC, which Android plays natively.
Does converting ALAC to MP3 reduce quality?
Yes — MP3 is lossy. Converting from ALAC to MP3 permanently discards some audio data. At 320 kbps, the result is excellent for most listening. Since ALAC is lossless, you are starting from the best possible source.
Convert ALAC
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Last updated: March 28, 2026