Mix notes
Understand loudness before changing your master
How it works
Integrated LUFS describes loudness across the track, with frequency weighting and gates that keep silence from dominating the measurement. Mixchecker estimates it using sample-rate-specific K weighting, overlapping 400 millisecond blocks and absolute and relative gates. Load your final export and allow analysis to finish. Sample peak in dBFS and estimated true peak in dBTP sit alongside loudness because similar LUFS readings can hide very different transient and reconstruction peaks.
Use normalization as context
Spotify Normal playback uses −14 LUFS as a normalization reference, not a mandatory mastering level. The platform card estimates the gain change for a single track and limits upward gain by available true-peak headroom. Album playback, device settings and players can behave differently. Do not compress a dynamic recording merely to hit that reference, or assume that a louder master will remain louder after normalization. Check the supplied official sources when preparing a release.
Separate advice from readiness
Spotify’s suggested −1 dBTP headroom, or −2 dBTP for masters louder than −14 LUFS, is optional mastering advice here. Apple headroom guidance is also separate and unscored; Apple Music is not assigned a universal −14 or −16 LUFS acceptance target. The general readiness calculation does not deduct points for ignoring these recommendations. If you choose to follow a platform recommendation, adjust export level or limiting deliberately and measure the new file instead of treating normalization as an approval test.
Know what this meter cannot hear
A reading cannot tell you whether limiting sounds musical, whether a vocal is masked or whether an encoded version distorts. True peak is an estimate, not an AAC audition or certified meter result. Clips shorter than 400 milliseconds and audio below the loudness gate have no meaningful integrated value. Resampling and unsupported layouts are reported. Compare references at matched listening levels in your DAW and judge the tradeoff between density, punch and fatigue by ear.
Frequently asked questions
Must I master to −14 LUFS?
No. Spotify Normal uses it as a playback reference. Suitable mastering loudness depends on the recording and destination, not a universal quality threshold.
Is LUFS the same as true peak?
No. LUFS estimates perceived loudness over time; dBTP estimates the maximum reconstructed waveform level. Sample peak uses dBFS.
Does Apple Music use the same target?
Do not assume so. Sound Check behavior is distinct, and this tool does not invent a universal Apple loudness acceptance gate.
Why can there be no LUFS value?
Silence, below-gate audio, unsupported channel layouts or clips shorter than a complete 400 ms block can prevent a meaningful estimate.