learn.howToCalculate
learn.whatIsHeading
Converts between power ratios and decibel scale for audio, RF, and other applications. Logarithmic scale matches human perception.
Formule
dBm = 10 × log10(P ÷ 0.001)
- P
- P value — Variable used in the calculation
Stapsgewijze handleiding
- 1dBm = 10 × log10(P ÷ 0.001)
- 2dBW = 10 × log10(P)
- 3Reverse: power (watts) = 10^(dBm ÷ 10) ÷ 1000
- 4Every 3 dB ≈ 2× power
- 5Every 10 dB ≈ 10× power
Uitgewerkte voorbeelden
Invoer
Power 1W
Resultaat
30 dBm
Veelgemaakte fouten om te vermijden
- ✕Confusing dBm (power) with dBV (voltage) with dBu (relative to 0.775V)
- ✕Adding dBm values instead of multiplying power
Veelgestelde vragen
Why use decibels instead of watts?
Logarithmic scale compresses large ranges (1W to 1MW becomes 30 dBm to 60 dBm), easier comparison.
What's typical dBm for audio and RF?
Audio -20 to +4 dBu typical; WiFi transmit +17 to +30 dBm; cellular -30 to +33 dBm.
Klaar om te berekenen? Probeer de gratis Decibelm W-rekenmachine
Probeer het zelf →