Convert ALAC to AAC — Free Online Converter

ALAC (Apple Lossless Audio Codec) stores bit-perfect audio in M4A containers, achieving roughly 50% compression compared to raw PCM while preserving every sample. AAC (Advanced Audio Coding) is the industry-standard lossy codec, delivering transparent quality at 256 kbps with 10:1 compression ratios. Both ALAC and AAC live in the M4A container — they share the same file format, metadata system, and Apple ecosystem integration.

Converting ALAC to AAC trades lossless quality for dramatically smaller file sizes while remaining within the same M4A container ecosystem. This is the standard workflow for creating distribution copies from lossless masters on Apple platforms.

ALAC files at CD quality occupy roughly 5-6 MB per minute, while AAC at 256 kbps needs only about 2 MB per minute — a 60-70% size reduction with virtually indistinguishable quality. For mobile devices with limited storage, portable music players, and streaming, AAC provides the practical balance of quality and size.

Since both codecs share the M4A container, all metadata — album art, lyrics, chapter markers, iTunes tags, and library organization — transfers perfectly with zero mapping issues. This makes ALAC-to-AAC the smoothest possible lossy conversion within the Apple ecosystem.