Decibels relative to 1 milliwatt. 0 dBm = 1 mW. Positive values are above 1 mW.

How do I convert dBm to watts?

P(W) = 10^((dBm - 30)/10) or use the calculator for common values.

Dbm To Watts Calculator

Dbm To Watts - Perform scientific calculations with precision and accuracy.

Real-time power conversion

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Power (dBm)

dBm

Power (Watts)

dBm (decibel-milliwatts) is a logarithmic unit of power, expressed relative to one milliwatt (1 mW = 0.001 W).

Watts (W) is the standard unit of power in the International System of Units (SI).

dBm expresses power in decibels relative to 1 milliwatt. Converting to watts aids hardware sizing and RF measurements.

20 dBm → P(mW) = 10^2 = 100 mW → P(W) = 0.1 W.

Negative dBm?
Indicates power below 1 mW.

dBW vs dBm?
dBW references 1 W; dBm references 1 mW.

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