MotionShine01 / Measure
Integrated LUFS
The sound is K-weighted and measured in 400 ms blocks, ignoring silence and quiet stretches, as BS.1770 describes.
Free tool
Loudness normalizer, LUFS made easy.
Drop a song, a podcast episode or a voice-over and see its loudness in LUFS, measured the way the ITU-R BS.1770 standard describes, with its true peak. Pick a target and the whole file is set to it with one even gain; if that would push the peaks too high, a look-ahead limiter holds them under the ceiling. Save MP3 or WAV. It runs in this tab, so your file is never uploaded.
Targets read on Spotify’s and Apple’s help pages and the EBU’s R 128 page on 17 October 2026.
Save
The sound is measured and changed in your browser. It is never uploaded.
How it works
Measured, set, kept clean.
02 / Set
One even gain
The whole file moves up or down by the same amount, so its dynamics stay as they were.
03 / Guard
True peak ceiling
Peaks between samples are checked too; a look-ahead limiter catches any above the ceiling.
Questions
Good to know.
Which target should I pick?
Spotify’s help for artists suggests mastering at -14 LUFS with the true peak under -1 dB (or under -2 dB for masters louder than -14). Apple’s audio requirements for podcasts ask for about -16 LKFS, plus or minus 1 dB, with the true peak at no more than -1 dB. EBU R 128 sets -23 LUFS for broadcast.
What is the difference between LUFS and LKFS?
None in value: both name the same loudness unit from ITU-R BS.1770, one in EBU’s naming and one in the ITU’s.
Why is the result sometimes a little under the target?
When a quiet file has very loud peaks, reaching the target would mean squashing them hard. The page lifts it at most 6 dB more than the plain gain, so it can stop a little under. A lower target keeps the sound more natural.
How is this different from the volume booster?
The volume booster raises the level by decibels or to the loudest point. This page sets the loudness people hear, the measure streaming services use.
Is my file uploaded?
No. Everything happens in this tab.