What is LUFS? A practical guide to audio loudness

LUFS is a measure used to assess how loud audio feels. It serves a different purpose from peak level.

Peak level and loudness

A peak meter shows how high the signal reaches at a particular moment. LUFS considers loudness over time. Two songs with the same peak level may feel very different because of their density and dynamics.

Integrated LUFS

Integrated LUFS is commonly used to assess loudness over a whole track. It follows defined measurement rules to evaluate the recording as a whole, rather than just an intro or chorus, and is useful when comparing tracks.

Matching a number is only part of the job

Excessive compression or limiting to reach a target can remove the impact of transients or make the bass sound unnatural. Loudness measurements inform a decision; they do not measure musical quality.

What to listen for

Compare the original and adjusted versions at similar perceived levels. Listen to the position of the vocal or main melody, the bass, brief sounds such as snare hits, and the sense of space in quieter passages. Try another playback setup as well as your usual headphones to hear the result from a different perspective.