dBm Volts Watts Conversion

dBm Volts Watts Conversion

dBm is defined as power ratio in decibel (dB) referenced to one milliwatt (mW). It is an abbreviation for dB with respect to 1 mW and the "m" in dBm stands for milliwatt.


Power level L dBm ref 1 mW
Voltage V V RMS
Watt W watts
Impedance Z Ω


Here is an Excel spreadsheet containing the calculations:
dBm to Voltage to watts Microsoft Excel
and a conversion table here:
EMC Related Formulas Adobe Acrobat

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