LUFS stands for "Loudness Units Full Scale" and is a measure of the loudness of audio signals. It was developed to make the loudness of audio files comparable on different platforms and is often used in mastering. LUFS is expressed in dB ( Decibel ) and takes into account not only the absolute volume but also the dynamics of the audio signal. This means that LUFS adjusts the loudness of audio files in relation to their dynamics measures, instead of only evaluating them according to their absolute loudness. This can help music play well on different platforms and speaker systems and have proper tonal balance. What is LU? LU stands for "Loudness Units" and is a measure of the loudness of audio signals. It was developed to make the loudness of audio files comparable on different platforms and is often used in mastering. LU is measured in dB (decibels) and takes into account not only the absolute volume but also the dynamics of the audio signal. This means that LU measures the loudness of audio files in terms of their dynamic range, rather than simply evaluating them based on their absolute loudness. This can help music play well on different platforms and speaker systems and have proper tonal balance. LU is a derived quantity based on the full scale concept, which refers to the maximum loudness of an audio signal. The term "Loudness Units Full Scale" (LUFS) refers to loudness in relation to full scale. What types of loudness measurement are there within LUFS? Short term loudness This is the briefly measured loudness. This happens over a period of 3 seconds. Momentary loudness This is the current loudness which is measured within 400ms. Integrated loudness Integrated Loudness determines the average loudness over the entire playing time. A "relative gate" is usually used here. This means that signal which is below a certain limit will not be used to calculate the average loudness. According to EBU 128, for example, the limit is -23 LUFS. volume and loudness Loudness is often confused with loudness. In short - the volume is set on your end device such as the stereo system or smartphone. You can adjust the volume there. Loudness is also a subjective and relative term . But when we talk about loudness, it is a fixed, measurable value that is not only relevant for the sound in the master, but also for that Streaming on Spotify, Youtube and Co . The measurement is usually done with a plugin in your DAW. The Youlean plugin is free and can be easily integrated into any audio workstation in the studio. So you have the volume in the mix with the meter very well under control.

LUFS - Loudness Units Relative to Full Scale

LUFS is the standard loudness measurement for audio material. It is used to define, measure and compare perceived loudness, whether in online mastering for streaming services or in CD production. LUFS is now firmly established across professional audio.

What is LUFS?

LUFS stands for Loudness Units relative to Full Scale. It is a standardized way to measure the perceived loudness of audio signals and make loudness comparable across platforms.

LUFS is measured in dB and considers both level and the dynamics of the audio signal. Instead of judging a track only by its absolute peak level, LUFS evaluates loudness over time. This helps music translate more consistently across streaming platforms, speaker systems and playback environments.

What is LU?

LU stands for Loudness Unit. One LU corresponds to a 1 dB change in measured loudness. LU is used to describe loudness differences, while LUFS expresses loudness relative to full scale.

Because LUFS is referenced to full scale, it is especially useful in digital audio, broadcast and streaming. It gives engineers a practical target for perceived loudness without ignoring dynamics.

Which LUFS loudness measurements are used?

Short-term loudness

Short-term loudness measures loudness over a three-second window.

Momentary loudness

Momentary loudness shows the current loudness over a very short 400 ms window.

Integrated loudness

Integrated loudness calculates the average loudness over the full playback time. A relative gate is usually used so quiet passages below a defined threshold are not included in the average. Under EBU R128, for example, the gate is based around -23 LUFS.

Volume and loudness

Volume and loudness are often confused. Volume is the level you set on a playback device such as a stereo system or smartphone. Loudness, in the LUFS sense, is a measurable value that matters not only for the sound of the master but also for streaming on Spotify, YouTube and similar platforms. In practice, LUFS is usually measured with a DAW plugin; Youlean Loudness Meter is a popular free option for checking loudness in the mix and mastering process.

Streaming master for your tracks?

Why is LUFS so important?

LUFS has become more important than ever because streaming platforms and broadcasters normalize playback loudness. This changed the old loudness war, where productions competed mainly by becoming louder.

The loudness war became possible through digital mastering tools that allowed engineers to push converters and limiters very hard. Some productions used deliberately driven hot masters, accepting distortion or reduced dynamics to sound louder than competing releases.

Classifying loudness in mixing: Our Mixing Guide shows how LUFS, dynamics and headroom can already be prepared properly in the mix.

As songs and albums became louder, differences between releases grew and playback became less consistent. LUFS normalization helps reverse that trend. When streaming providers or broadcasters define a loudness target below the technical maximum, listeners can play songs one after another without constantly adjusting the volume.

This reduces the pressure to win through loudness alone and encourages better quality within a defined loudness range. The result benefits both listeners and the music.

More info about LUFS

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