Online Audio Loudness Analyzer
Open a file and get its loudness in LUFS, its true peak in dBTP and its loudness range, measured in your browser. Your audio never leaves your device.
What Are LUFS and True Peak?
LUFS (Loudness Units relative to Full Scale) describe how loud audio sounds, not just how high its waveform reaches. The measurement follows the ITU-R BS.1770 standard: the signal is weighted to match the sensitivity of the ear and averaged over the whole file, and silent passages are left out. True peak (dBTP) is the highest level the signal reaches between the samples, found by oversampling the audio four times. It can be higher than the sample peak that ordinary meters show, which is why a file that peaks at -0.3 dBFS can still distort after conversion to MP3 or AAC.
How to Read the Results
- Integrated loudness: the loudness of the whole file. This is the number streaming platforms use for normalization.
- True peak: keep it at or below -1 dBTP so the file doesn’t clip when it is converted to a lossy format.
- Loudness range (LRA): how much the loudness varies. A low value means a steady level; a high value means a big difference between quiet and loud passages.
- Max short-term and max momentary: the loudest 3-second and 0.4-second stretches of the file.
- Peak-to-loudness ratio (PLR): the gap between true peak and integrated loudness. It tells you how far you can raise the file before the peaks reach the ceiling.
The numbers can differ by a few tenths of a decibel from other meters, because the browser converts the file to your device’s sample rate before measuring.
Who Is It For?
Musicians checking a master before sending it to a distributor, podcasters aiming for -16 LUFS, and video editors who want consistent loudness between clips. To change the level afterwards, use the Sound Optimizer; the guide How to Normalize Audio Without Clipping explains the method.