Enter the total dBm into the calculator to convert to units of watts. This calculator can also determine db given the watts.

DB to Watts Formula

The following formula is used to convert dBm to watts.

W = 10^((dBm-30)/10))

  • Where W is the power in watts
  • dBm is the decibel-milliwatts

To calculate watts from db, subtract 30 from the dbm, divide the result by 10, then take a value of 10 and raise it to the power of the result calculated previously.

Db to Watts Definition

Converting dB to watts is actually the process of converting decibel-milliwatts to watts since decibel in itself is just a unitless factor.

Db to Watts Example

How to convert dB to watts?

  1. First, determine the total number of dBm.

    Calculate or measure the total decibel-milliwatts. This is a measure of power of the system.

  2. Next, calculate the watts.

    Convert the dBm into watts using the equation above.


What are watts?

Watts are a measure of power which is a unit that describes energy over time.