dB/dBm/Watts Converter
Convert between power units used in RF and telecommunications.
Quick dB Addition/Subtraction
Common Power Levels
| dBm | Watts | Application |
|---|---|---|
| -110 | 0.1 pW | Weak GPS signal |
| -80 | 10 pW | Good WiFi signal |
| -50 | 10 nW | Strong WiFi signal |
| 0 | 1 mW | Bluetooth Class 2 |
| 20 | 100 mW | WiFi typical |
| 30 | 1 W | WiFi max/handheld radio |
| 37 | 5 W | Amateur VHF/UHF |
| 43 | 20 W | Cellular base station |
| 50 | 100 W | Amateur HF/FM broadcast |
| 60 | 1 kW | AM broadcast |
Decibel Quick Reference
Key Conversions
- +3 dB = 2x power
- +10 dB = 10x power
- +20 dB = 100x power
- -3 dB = 1/2 power
- -10 dB = 1/10 power
Formulas
dBm = 10 × log₁₀(P/1mW)
P(mW) = 10^(dBm/10)
P(mW) = 10^(dBm/10)
dBm vs dBW
dBW = dBm - 30
dBm = dBW + 30
dBm = dBW + 30