Watts (W) to decibel-milliwatts (dBm), power conversion calculator.
Enter the power in watts and press the Convert button:
dBm to watts conversion calculator ►
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
Convert 20 watts to dBm:
P(dBm) = 10 ⋅ log10(1000⋅20W) = 43.0103dBm
| 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 |