Watt-to-dB-converter

Watt to dB Calculator

In this post we convert a power level from Watt to deciBel (dB).

Watt is an absolute unit of power. dB is a relative measure. In this case we consider a reference power Pref when converting Watt to dB. The input power Pw is referenced to this value when making the calculation.

🛜 Use this calculator to convert Watt to dBm. dBm stands for deciBel relative to one milliwatt (Note the ‘m’). Both Watt and dBm are absolute numbers.

Calculator

Enter

  • Power in Watt
  • Reference Power in Watt

The tool will calculate the dB value

🔁 dB to Watt

Formula

PdB is determined by the following formula:

PdB = 10*Log10 (Pw/ PR)

Where

  • PW is the power specified in Watt
  • PR is the reference power in Watt

Example Calculation

The picture below shows the sound power level in dB vs the sound power level in Watt (W)

In this case PR = 10-12 Watt

  • 1 Watt of power is equivalent to 120 dB
  • 0.001 Watt of power is equivalent to 90 dB

Related Calculators