Volt (V) to dBV Formula and Calculator

This tool converts from V (Volt) to dBV (deciBel Volt).

🔁 dBV to V

Formula

dBV = 20*Log10 (VRMS)

Example Calculations

  • A value of 10 V is equivalent to 20 dBV
  • A value of 1.122 V is equivalent to 1 dBV

Background

dBV stands for deciBel relative to 1 Volt.

Specifically it is 1 Volt RMS (Root-mean-square*) and not average, peak or peak-to-peak. Using the tool above: 1 Volt is equivalent to 0 dBV and 2 Volt is equivalent to 6.02 dBV.

*RMS voltage can be calculated using a closed form expression for certain waveform types (sine, square, etc.) or a sequence of measured values for an arbitrary waveform.

Based on the definition of RMS voltage below, it is always a positive quantity greater than or equal to zero.

VRMS = √(1/n)(V12 +V22 + … + Vn2)

For

  • VRMS > 1, the equivalent value of dBV will be positive.
  • VRMS < 1, the equivalent dBV will be negative.

The exception is VRMS = 0 where the equivalent dBV is infinitesimally small or -∞.

What’s the difference between dB and dBV?

deciBel or dB represents a ratio of two amplitude or power levels. It provides a measure of how large one number is relative to another. 

For example:

  • A power ratio of 100 for example is equivalent to 20 dB. Using the ratio to dB calculator.
  • If the output level of an amplifier is 40 dB relative to the input, it means that the input has been amplified 10000 times. Using the dB to times calculator.

The dB scale presents a convenient way to represent both very large and very small numbers. It’s used by engineers in various fields such as Radio Frequency, Optical and Audio.

DeciBel Volt or dBV represents an absolute quantity. The reference in this case is 1 Volt – hence the suffix ‘V’ (note that it has to be capital V and not lowercase). As with dB, it is used to represent very large and small numbers.

Where is dBV used?

dBV is used in the world of Audio. It is consistent with measures for sound intensity and the Log scale is more representative of how the human ear responds to sound.

Related Calculators

  • dBV to mV
  • VRMS to VPP – Convert RMS Voltage to Peak-to-Peak Voltage for a sinusoidal waveform
  • VRMS to dBm – Convert RMS Voltage to Power in dBm
  • dBV to dBu