NC-NR Calculator

With our NC‑NR tool, you can quickly and precisely determine the room acoustic assessment of technical units based on the sound power level. Enter the unit's sound data as well as the room dimensions and room type, and automatically receive a chart showing which Noise Rating (NR level) or Noise Criteria (NC level) is achieved.

Acoustic Assessment Made Easy

The tool is ideally suited for estimating NC and NR levels and enables a characteristic description of the noise level of technical equipment. It is based on the international sets of curves according to the ISO definition, which are regularly used in technical building planning.

Features of the NC‑NR Tool

  • Input of sound power in octave bands
  • Input of room dimensions
  • Input of the room reverberance (live/medium live/average/medium dead/dead)
  • Automatic determination of the corresponding NR and NC curves
  • Display as a clear chart with direct output of the resulting NR/NC level
  • Optional data sheet export function for documentation

Calculate NC and NR Levels Now

The NC‑NR tool supports engineers, planners, and acousticians in the rapid assessment of noise levels – directly in the browser, without any additional software installation.

Go to the NC-NR Calculator