---
title: "LUFS"
url: https://postproduction.studio/en/glossary/lufs
language: en
description: "LUFS (Loudness Units relative to Full Scale, sometimes called LKFS in the older ITU standard) is the measurement unit for integrated loudness — the perc..."
updated: 2026-10-25
---

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# LUFS

LUFS (Loudness Units relative to Full Scale, sometimes called LKFS in the older ITU standard) is the measurement unit for integrated loudness — the perceived volume of audio content averaged over its duration, weighted by the K-frequency curve to match human hearing sensitivity. The development of LUFS-based standards solved a real broadcasting problem: commercials sounded much louder than programs even when peak levels matched, because peak amplitude poorly correlates with perceived loudness. The ITU-R BS.1770 standard defined the loudness measurement algorithm, and EBU R128 (Europe), ATSC A/85 (US TV), and platform-specific targets (Netflix -27 LUFS short-form, -27 LUFS Atmos integrated; Apple Music -16 LUFS; Spotify -14 LUFS; YouTube -14 LUFS; broadcast typically -23 LUFS integrated) define delivery targets. Modern audio meters display three measurements: Momentary (400ms sliding window, instantaneous reading), Short-term (3-second sliding window), and Integrated (full-program average from start to end). A typical mix is judged by Integrated LUFS versus the target, plus Loudness Range (LRA, the dynamic range) and True Peak (the actual maximum samples, not the integer-sample peaks). Mixers ensure their final masters land at platform targets, applying limiting and loudness adjustment where needed without overcompressing dialogue. Tools: iZotope Insight, Waves WLM, NUGEN VisLM, Pro Tools' built-in loudness meter. Reference: EBU R128, ITU-R BS.1770.

Sound, DeliverySound Mixer, Mastering EngineerMixing, Delivery

## Related terms

[Loudness](https://postproduction.studio/en/glossary/loudness)[QC (Quality Control)](https://postproduction.studio/en/glossary/qc-quality-control)[Mastering](https://postproduction.studio/en/glossary/mastering)

Integrated loudness targets (LUFS / LKFS) for major delivery platforms. Music streaming sits 9-13 LU louder than broadcast/cinema reference.

## Articles covering this term

* [Audio Mastering and Loudness Normalization

  Technical exploration of audio mastering, LUFS normalization, broadcast standards and compliance processes in post-production.](https://postproduction.studio/en/sound/audio-mastering)
* [Audio monitoring: loudness, spectrum, phase

  Discover audio measurement tools in post-production. Master LUFS loudness, true peak, frequency spectrum, phase, and broadcast delivery standards.](https://postproduction.studio/en/tools/audio-monitoring)
* [Sound mixing: balancing the soundtrack

  Mixing synthesizes sound elements into a coherent soundtrack. Balance, processing, spatialization and validation for post-production.](https://postproduction.studio/en/sound/sound-mixing)
* [Audio post tools: Pro Tools, Nuendo, Reaper

  A comprehensive guide to digital audio workstations (DAWs) and audio post-production tools. Explore Pro Tools, Nuendo, Reaper, plugins, and hardware control surfaces.](https://postproduction.studio/en/tools/audio-post-tools)
* [Music and scoring: the role of musical sound

  Exploration of music's role in post-production: composition, synchronization, rights and integration in final mixing.](https://postproduction.studio/en/sound/music-scoring)
* [Quality control and deliverable compliance

  Complete guide to quality control (QC) in post-production. Master AQC tools, video/audio standards, metadata, and deliverable compliance workflows.](https://postproduction.studio/en/formats/quality-control)