What Is Crest Factor?
Published · updated · by Loopin
Crest factor is the gap between your peak level and your average level. It is a single number that predicts whether a master will feel punchy or flat, and almost nobody looks at it.
The number and how to read it
Take your true peak in dBTP and subtract your integrated LUFS. A master at −1 dBTP and −14 LUFS has a crest factor of 13. That figure is sometimes called PLR, peak-to-loudness ratio, and it is the same measurement.
Higher means more dynamic contrast between the loudest hits and the general level. Lower means the material is denser and the transients have less room above the average.
Typical values, by genre
Acoustic and jazz: 14–18. Rock and indie: 10–13. Pop: 8–11. Hip-hop and electronic: 6–9. Anything under about 5 is heavily limited and will usually sound flat regardless of how loud it measures.
These are not targets to hit, they are a sanity check. If your acoustic record is coming out at 7, something has squashed it that should not have.
It explains the "loud but small" problem
A master can measure loud and feel small at the same time, and crest factor is why. When the peaks come down to meet the average, drums stop reading as impacts and start reading as texture — the level is high but nothing is hitting.
This is the number to look at when a track sounds fine in isolation and disappears next to a reference. Loudness matched, the one with more crest factor almost always feels bigger.
Watch it fall as you push the limiter
The useful way to use it is as a live readout while you set your loudness target. Every decibel of extra limiting takes roughly a decibel off the crest factor, and there is a point in every track where the trade stops being worth it.
Note the figure before limiting and after. If you have gone from 14 to 6 to gain three decibels of loudness that streaming will normalise away, re-master at a saner target — you have paid a lot for nothing.
It is not a quality score
A crest factor of 7 is correct for dense electronic music, where the density is the sound. A crest factor of 16 on a pop single would sound underwhelming next to its peers. There is no universally good value.
Use it comparatively: against your own reference tracks in the same genre, and against your own earlier drafts. It answers "did I go too far", which is the only question it is good at, and it answers it precisely.
Frequently asked questions
How do you calculate crest factor?
True peak in dBTP minus integrated LUFS. A master at -1 dBTP and -14 LUFS has a crest factor of 13. It is also called PLR, peak-to-loudness ratio.
What is a good crest factor?
It depends on genre: 14-18 for acoustic and jazz, 10-13 for rock, 8-11 for pop, 6-9 for hip-hop and electronic. Under about 5 is heavily limited and usually sounds flat however loud it measures.
Why does my loud master sound small?
Low crest factor. When peaks come down to meet the average, drums stop reading as impacts and start reading as texture — the level is high but nothing hits. Compare level-matched against a reference to hear it.