Watts to dBm conversion calculator
Watts (W) to decibel-milliwatts (dBm), power conversion calculator.
Enter the power in watts and press the Convert button:
dBm to watts conversion calculator ►
How to convert watts to dBm
The power P(dBm) in dBm is equal to 10 times the base 10 logarithm of 1000 times the power P(W) in watts (W) divided by 1 watt (W):
P(dBm) = 10 ⋅ log10( 1000 ⋅ P(W) / 1W) = 10 ⋅ log10( P(W) / 1W) + 30
so
1W = 30dBm
Example
Convert 20 watts to dBm:
P(dBm) = 10 ⋅ log10(1000⋅20W) = 43.0103dBm
Watt to dBm conversion table
| Power (mW) | Power (dBm) |
|---|---|
| 0 W | not defined |
| 0+ W | -∞ dBm |
| 01 W | -20 dBm |
| 0.0001 W | -10 dBm |
| 0.001 W | 0 dBm |
| 0.01 W | 10 dBm |
| 0.1 W | 20 dBm |
| 1 W | 30 dBm |
| 10 W | 40 dBm |
| 100 W | 50 dBm |
| 1000 W | 60 dBm |
| 10000 W | 70 dBm |
| 100000 W | 80 dBm |
| 1000000 W | 90 dBm |