Audio
Lossless vs Lossy Audio: FLAC, WAV, MP3 and AAC Compared
Audio formats split into two camps: lossless (perfect quality, big files) and lossy (smaller files, some detail discarded). Knowing which is which stops you wasting space or quality.
Lossy vs lossless in one minute
Lossy formats (MP3, AAC, OGG) shrink audio by permanently discarding detail most people cannot hear. Lossless formats (FLAC, WAV) keep every bit of the original. Lossy wins on file size and is perfect for listening; lossless wins on fidelity and is the choice for editing, mastering, and archiving.
One key rule follows from this: converting a lossy file to a lossless format cannot restore quality that was already thrown away. The file just gets bigger. Lossless is only worth it when your source is lossless.
WAV: the uncompressed master
WAV stores raw, uncompressed audio - perfect quality, but very large files. It is the standard for recording, editing, and mastering in audio software. You would rarely distribute WAV; you edit in it and then export something smaller.
FLAC: lossless, but compressed
FLAC gives you the same perfect quality as WAV at roughly half the size, because it compresses losslessly. It also stores metadata and album art. For music libraries and archives where quality matters, FLAC is the smart middle ground.
MP3 and AAC: the everyday formats
MP3 is the universal lossy format - it plays on everything and files are small. AAC, used by Apple Music and most streaming services, generally sounds slightly better than MP3 at the same bitrate. For casual listening, podcasts, and sharing, both are excellent; the difference is compatibility (MP3 wins) versus efficiency (AAC edges ahead).
Which format should you pick?
It comes down to what you are doing:
- Recording or editing: WAV.
- Archiving music at full quality: FLAC.
- Listening and sharing everywhere: MP3.
- Apple devices and modern streaming: AAC.