Engineering Calculators

Distance Attenuation Calculator

Sound pressure level measured at the reference distance.

Formula Reference

Inverse-Square Law (Distance Attenuation)

SPL2=SPL1−20log⁡10(d2d1)SPL_2 = SPL_1 - 20 \log_{10}\left(\dfrac{d_2}{d_1}\right)

SPL_1 = reference sound pressure level (dB), d_1 = reference distance (m), d_2 = target distance (m), SPL_2 = sound pressure level at the target distance (dB).