What Are the Loudness Specs for Streaming?
Streaming platforms use automated loudness normalization algorithms to maintain consistent listening volume across tracks, requiring audio engineers to master according to specific integrated loudness targets and true peak ceilings. Delivering music that ignores these guidelines can result in automatic volume attenuation, loss of dynamic punch, or distortion caused by lossy codec transcoding. Understanding the specifications across services ensures masters retain their fidelity and dynamic impact across all distribution channels.
Key Loudness Metrics Explained
Modern loudness standards rely on standards established by the International Telecommunication Union (ITU-R BS.1770) rather than simple peak or RMS values.
- Integrated LUFS (Loudness Units relative to Full Scale): Measures the perceived average loudness of an entire song from start to finish using frequency weighting that mimics human hearing.
- True Peak (dBTP): Measures the actual peak levels of the reconstructed analog waveform. This detects inter-sample peaks that standard digital peak meters miss, which cause distortion when audio is encoded into lossy formats such as AAC or Ogg Vorbis.
- Loudness Range (LRA): Measures the statistical dynamic range between the quieter and louder sections of a track, indicating overall dynamic variation.
Platform Delivery Targets
Each major digital service provider (DSP) applies its own playback reference levels and peak limits.
| Platform | Integrated Loudness Target | Recommended True Peak (dBTP) | Transcoding Notes |
|---|---|---|---|
| Spotify | -14 LUFS | -1.0 dBTP (-2.0 dBTP if louder than -14 LUFS) | Uses ReplayGain and ITU-R BS.1770; normalizes both up and down. |
| Apple Music | -16 LUFS | -1.0 dBTP | Uses Apple Sound Check; applies gain offsets without limiting. |
| YouTube | -14 LUFS | -1.0 to -2.0 dBTP | Only attenuates louder tracks; does not boost quieter tracks. |
| Amazon Music | -14 LUFS | -1.0 dBTP | Normalizes volume based on BS.1770 standards. |
| Tidal | -14 LUFS | -1.0 dBTP | Primarily applies album normalization; preserves original peaks on quiet tracks. |
| SoundCloud | None (No normalization) | -1.0 to -2.0 dBTP | Plays back original file levels; transcodes to 64 kbps Opus / 128 kbps MP3. |
Production and Delivery Best Practices
While target numbers serve as playback references, production choices should still prioritize the artistic needs of the genre.
- Leave Adequate True Peak Headroom: Set final limiter ceilings to at least -1.0 dBTP (or -1.5 to -2.0 dBTP for heavily saturated, dense mixes) to ensure inter-sample distortion does not occur during AAC or MP3 encoding.
- Treat LUFS Targets as References, Not Hard Rules: Many commercial pop, electronic, and rock masters sit between -9 and -7 LUFS for specific saturation and transient density. While platforms turn these tracks down to -14 or -16 LUFS, the perceived punch and density remain.
- Avoid Over-Squashing: Compressing a master excessively to hit extreme loudness can cause a track to sound small, flat, and fatigued when turned down by the normalization algorithm alongside more dynamic material.
- Deliver High-Resolution PCM Files: Export final masters at 24-bit depth using the native mix sample rate (minimum 44.1 kHz) in uncompressed WAV or AIFF formats to give distributors maximum fidelity before platform encoding.