Phon to Sone Calculator

About this calculator

Phon measures perceived loudness relative to a 1 kHz reference tone at the same sound pressure level (accounting for how the ear's sensitivity varies by frequency), while sone is built so that a doubling of the sone value means a doubling of perceived loudness — a property phon doesn't have. Above 40 phon, the two relate by sone = 2^((phon − 40)/10), with 40 phon fixed at exactly 1 sone.

Acousticians and audio engineers use sone when a linear “twice as loud” scale matters more than a raw decibel-style figure, and manufacturers of appliances, HVAC units, and power tools often publish noise ratings in sone precisely because it maps more directly onto how loud a product feels to a listener.