SInES Tools: Zwicker Loudness Meter

SInES Tools: Zwicker Loudness Meter (Loudness Measurement according to Zwicker ISO 532B, 1975)

1. Upload an audio file (.wav or .mp3) or load the Example Signal.
2. Optional: select the Sound Field (Free field or Diffuse field) depending on how the sound was recorded.
3. Optional: enter calibration data for the measuring microphone (at how many dBSPL was it calibrated at 1000 Hz?)
4. Select the Evaluation Mode (calculate the 'Mean' over the entire file, find the 'Maximum' loudness, or select a specific 'Time Frame'
via the slider or chart).
5. Use the Copy or Save as Excel buttons below to export the ISO 532B critical bands data for further analysis.

1. Audio Input

Audio File (.wav, .mp3)

calculating...

Example Signal

2. Evaluation Settings

Sound Field

Ref / Meas (dB_SPL / dB_FS)

Evaluation Mode

Time Frame

3. Results

Loudness N

                    – sone
                

Loudness Level L_N

                    – phon
                

Evaluated:	–
N5 (exceeded 5%):	–
Core loudness:	–
Masked part:	–

Loudness-Pitch Diagram Hover over a band for details.

Specific loudness (N)
Upper slope
Core loudness
Masked core

Loudness over time Click/drag to select time

Critical Bands (ISO 532B) Level Note

Band	Pitch / Bark	Frequency / Hz	Width / Hz	Δf_G / Hz	Level L_G / dB	Core N′ / sone/Bark	Masking

Zwicker Loudness Meter © 2026 by Christoph Reuter and SInES (last modified: 3.11.2026) is released under MIT License
How to cite: Reuter, C. (2026). SInES Tools: Zwicker Loudness Meter. Web Application https://sinestools.univie.ac.at/zwickerloudness.htm