Decibel-milliwatt (dBm)

Power level relative to one milliwatt: 10 times the base-10 logarithm of the power in milliwatts. 0 dBm is 1 mW and 30 dBm is 1 W.

What is a decibel-milliwatt?

Symbol: dBm
Quantity: Power Level (dBm, dBW)
Unit system: other
Definition: Power level relative to one milliwatt: 10 times the base-10 logarithm of the power in milliwatts. 0 dBm is 1 mW and 30 dBm is 1 W.
Exact: Yes, the value is exact by definition
Source: IEC 60027-3:2002, Logarithmic and related quantities, and their units

Common applications

Used for Wi-Fi, cellular and radio signal power and for optical fiber power. A router sending 20 dBm transmits 100 mW; a received signal of −60 dBm is 1 nW.

Decibel-milliwatt in other power level (dbm, dbw) units

mW = 10^(dBm ÷ 10)Decibel-milliwatt to Milliwatt converter
W = 0.001 × 10^(dBm ÷ 10)Decibel-milliwatt to Watt converter
kW = 0.000001 × 10^(dBm ÷ 10)Kilowatt
µW = 1000 × 10^(dBm ÷ 10)Decibel-milliwatt to Microwatt converter
dBW = dBm − 30Decibel-milliwatt to Decibel-watt converter

Decibel-milliwatt quick reference

Decibel-milliwatt in other units
Decibel-milliwatt	Milliwatt	Watt	Microwatt
-60 dBm	= 0.000001 mW	= 1e-9 W	= 0.001 µW
-30 dBm	= 0.001 mW	= 0.000001 W	= 1 µW
-20 dBm	= 0.01 mW	= 0.00001 W	= 10 µW
-10 dBm	= 0.1 mW	= 0.0001 W	= 100 µW
0 dBm	= 1 mW	= 0.001 W	= 1000 µW
3 dBm	≈ 1.995262315 mW	≈ 0.001995262315 W	≈ 1995.262315 µW