# mW to dBm Conversion

## mW to dBm conversion calculator

Enter the power in mW and press the Convert button:

 Enter power in milliwatts: mW dBm result: dBm

dBm to mW conversion calculator ►

#### mW to dBm

A milliwatt (mW) is one thousandth of a watt (W), or there are 1000 milliwatts in a watt. The watt is an SI derived unit of power. One watt is one joule of energy per second.

dBm or dBmW (decibel-milliwatts) is a unit of level used to indicate that a power level is expressed in decibels (dB) with reference to one milliwatt (mW). It is used in radio, microwave and fiber-optical communication networks as a convenient measure of absolute power because of its capability to express both very large and very small values in a short form compared to dBW, which is referenced to one watt (1000 mW).

#### How to convert mW to dBm

The power P(dBm) in dBm is equal to 10 times the base 10 logarithm of the power P(mW) in milliwatts (mW) divided by 1 milliwatt (mW):

P(dBm) = 10 ⋅ log10( P(mW) / 1mW)

So,

1mW = 0dBm

#### Example

Convert 20mW to dBm:,

P(dBm) = 10 ⋅ log10( 20mW / 1mW) = 13.0103dBm

#### mW to dBm conversion table

Power (mW) Power (dBm)
0+mW -∞ dBm
0.01 mW -20 dBm
0.1 mW -10 dBm
1 mW 0 dBm
2 mW 3.0103 dBm
3 mW4.7712 dBm
4 mW 6.0206 dBm
5 mW 6.9897 dBm
6 mW 7.7815 dBm
7 mW 8.4510 dBm
8 mW 9.0309 dBm
9 mW 9.5424 dBm
10 mW 10 dBm
100 mW 20 dBm
1000 mW 30 dBm
10000 mW 40 dBm
100000 mW 50 dBm
1000000 mW 60 dBm
10000000 mW 70 dBm
100000000 mW 80 dBm
1000000000 mW 90 dBm
10000000000 mW 100 dBm

dBm to mW conversion ►