Gain to dB Calculator

The two calculators below convert power and voltage gain to a dB (deciBel) value.

Power Gain to dB

Formula

GdB = 10*log10(Pout/Pin)

Voltage Gain to dB

Formula

GdB = 20*log10(Vout/Vin)

This assumes the input and output impedance is the same.

arrow dB to Gain Calculator