Quick Reference
| Parameter | Value | Notes |
|---|---|---|
| Integrated loudness | -16 LUFS (Sound Check) | EBU-gated per ITU-R BS.1770-4, typical range -18 to -14 LUFS |
| Max true peak | -1.0 dBTP | Headroom for AAC 256 kbps conversion |
| Clipping | Not allowed | Clipped samples are a hard fail in Apple ingestion |
| Sample rate | 44.1 / 48 / 88.2 / 96 kHz | All accepted; hi-res preferred for Digital Masters badge |
| Bit depth | 16-bit minimum | 24-bit recommended |
| Delivery codec | AAC 256 kbps (converted) | Apple encodes from your master; you deliver lossless |
How Apple Evaluates Your Master
Sound Check normalizes, clipping rejects
The two requirements have different weights. Loudness relative to the -16 LUFS Sound Check reference is corrected on playback and never blocks a release. Clipped samples do: a master that touches 0 dBFS is a hard fail at ingestion. QC priority follows from that - verify peaks first, then check where the loudness sits.
True peak, measured after your limiter
The -1.0 dBTP ceiling exists because Apple converts every master to AAC 256 kbps, and lossy encoding raises inter-sample peaks. Measure the final master with an oversampled true-peak meter (BS.1770-4 Annex 2). A limiter set to -1.0 dB output ceiling in sample-peak mode can still let true peaks through above the limit.
Loudness range is a mastering choice, not a spec
Apple publishes no LRA requirement. But because Sound Check level-matches everything to -16 LUFS, a master crushed to -9 LUFS gains nothing except the distortion it took to get there. The platform normalization makes dynamics free: the headroom you keep is the punch listeners hear after level matching.
Sample rate and the Digital Masters badge
Ingestion accepts 44.1, 48, 88.2 and 96 kHz at 16-bit or better. The Apple Digital Masters program prefers hi-res sources through certified mastering houses, but the technical checks on this page apply to every delivery regardless of badge status.
FAQ
Is the -16 LUFS target a rejection criterion?
No. Sound Check normalizes playback to roughly -16 LUFS, so loudness deviations are corrected on the listener side, not rejected at ingestion. What Apple does reject is clipping: files with samples at or above 0 dBFS fail. Loudness is advisory, clean peaks are mandatory.
Why does Apple use -16 LUFS when Spotify uses -14?
Different platform decisions, same measurement standard. Both compute integrated loudness per ITU-R BS.1770 with EBU gating; Apple simply normalizes to a quieter reference. A -16 LUFS master plays 2 dB quieter than the Spotify reference before normalization, and identical after it, since both platforms level-match playback.
What does the -1 dBTP ceiling protect against?
AAC encoding at 256 kbps reconstructs the waveform and can push inter-sample peaks above the highest sample value in your master. A file that sample-peaks at -0.2 dBFS can clip after conversion. Keeping oversampled true peak at or below -1.0 dBTP means the encoded AAC stays clean.
Do I need a hi-res master for Apple Digital Masters?
For the Apple Digital Masters badge, Apple prefers masters at high sample rates (88.2 or 96 kHz) delivered through a certified mastering workflow. For plain ingestion, 44.1 kHz / 16-bit is accepted. Either way the loudness and true peak requirements on this page are the same.
Does this spec apply to Apple TV+ deliveries?
No. Apple TV+ long-form content has its own delivery specification with dialogue-anchored loudness, closer to the Netflix model. This page covers music delivery to Apple Music and the iTunes Store via Apple Digital Masters.