FLAC to M4A audio converter

Worked example

Convert FLAC to M4A to fit a lossless library onto an Apple device: Chatcument writes lossy AAC, so choose 192 to 256 kbps.

Important: the M4A export here is AAC, not ALAC. If you need a lossless file for an Apple device, this is the wrong target, so keep the FLAC or choose WAV. For lossy delivery, AAC at 256 kbps from a FLAC is generally hard for most listeners to tell apart from the original on ordinary equipment.

Size math for a 4-minute track (240 s): the WAV is 42.3 MB and the FLAC typically 21 to 25 MB. As M4A it is 3.84 MB at 128 kbps, 5.76 MB at 192 kbps, 7.68 MB at 256 kbps and 9.6 MB at 320 kbps, so 256 kbps keeps roughly a third of the FLAC's size.

Scenario: a runner wants 300 tracks on a phone with little free space. At 256 kbps they need about 7.68 MB each, around 2.3 GB in all, against roughly 7 GB for the FLAC files. For 96 kHz sources choose 44100 or 48000 explicitly to avoid oversized, hard-to-play results.

Common mistake: assuming M4A means lossless because the extension is shared with ALAC. Fix: name the files with the bitrate, for example track_aac256.m4a. Check by comparing durations, listening to a quiet piano intro for graininess, and opening the file's info panel to confirm AAC.

sample.flac

sample.m4a

Hi-res bit depth and sample rate are not preserved by a lossy AAC encode.