dBm to Voltage and Power Calculator
Ω (Ohm)
50Ω (RF) |
75Ω (Video) |
1MΩ (Scope)
dBm
How it works?
In electronics and RF engineering, Power (P) and Voltage (V) are linked by the system Impedance ($R$). This calculator combines Ohm's Law with the definition of the Decibel to allow instant translation between signal strength (dBm) and physical voltage.
$$ P = \frac{V_{rms}^2}{R} $$
Ohm's Law for Power
$$ dBm = 10 \cdot \log_{10} \left( \frac{V_{rms}^2}{R \cdot 0.001} \right) $$ Voltage to dBm Conversion
$$ dBm = 10 \cdot \log_{10} \left( \frac{V_{rms}^2}{R \cdot 0.001} \right) $$ Voltage to dBm Conversion
Where:
- V_{rms} : Root Mean Square Voltage.
- R : Impedance (typically 50Ω for RF, 75Ω for Video).
- P : Power in Watts.
- dBm : Power ratio relative to 1 milliwatt.
Note on RMS: This calculator uses \(V_{rms}\). For a sine wave, \(V_{peak} = V_{rms} \times \sqrt{2}\) and \(V_{pp} = V_{peak} \times 2\).