The dBm to Vrms calculator allows you to convert power expressed in dBm into effective voltage (Vrms) for a given impedance.
This tool is useful for RF engineers, technicians and electronics enthusiasts to size and analyze circuits.
Formula used
P(W) = 10^(dBm / 10) / 1000
Vrms = √(P(W) × R)
Or :
dBm = power expressed in dBm
P(W) = power in watts
R = characteristic impedance of the circuit (Ω)
Vrms = effective voltage in volts
Explanation
The first step is to convert dBm power to watts using the formula P(W) = 10^(dBm/10)/1000.
Then the rms voltage Vrms is calculated by taking the square root of the product of the wattage and the circuit impedance.
This conversion is essential for analyzing signal levels in RF and electronic systems.
Calculation example
For a 10 dBm signal on an impedance of 50 Ω :
P(W) = 10^(10/10) / 1000 = 0.01 W
Vrms = √(0.01 × 50) ≈ 0.707 V
Benefits and Use
- Quickly converts dBm power into effective voltage for RF circuits.
- Useful for sizing and analysis of electronic and transmission systems.
- Makes it easy to verify signal levels in laboratories and in the field.
- Supports different impedance values to adapt to standard or specific circuits.
