Convert ALAC to AIFF — Free Online Converter

ALAC (Apple Lossless Audio Codec) stores lossless compressed audio in M4A containers at roughly 50% of raw PCM size. AIFF (Audio Interchange File Format) is Apple's uncompressed PCM container, created in 1988, storing raw audio at full fidelity with big-endian byte order. Both are Apple formats, but AIFF is the older, uncompressed standard.

Converting ALAC to AIFF decompresses the lossless audio to raw PCM samples. Since ALAC is mathematically lossless, the AIFF output is bit-for-bit identical to the original audio before ALAC compression. This conversion is needed when DAWs or audio systems require uncompressed AIFF input.

Some professional audio workflows and legacy DAW versions require uncompressed AIFF input. Logic Pro, GarageBand, and Final Cut Pro all handle ALAC directly, but third-party tools, hardware samplers, and some mastering chains may specifically require AIFF. Converting ALAC to AIFF satisfies these requirements with zero quality compromise.

AIFF files are also simpler for some audio analysis tools that expect raw PCM data without any compression layer. Scientific audio analysis, waveform inspection, and binary-level audio verification are easier with uncompressed AIFF.

FFmpeg decodes the ALAC stream from its M4A container, reversing the linear prediction and entropy coding to recover the original PCM samples, then writes them into an AIFF container with big-endian byte order. The output preserves the original sample rate (44.1 kHz, 48 kHz, 96 kHz, etc.), bit depth (16-bit or 24-bit), and channel layout exactly. The file size roughly doubles since ALAC compression is removed.