Decibel (voltage)

The decibel (dB) is used to express the ratio of two values on a logarithmic scale.

Formulas

The following formula can be used to calculate the decibel value for two voltages or one of the voltages.

L is the symbol for the decibel value and is measured in dB.
V is the symbol for voltage and is measured in volt (V).
V ref is the symbol for reference voltage and is measured in volt (V).

Calculator

Enter two values to calculate the third.