RF Calculator: Wavelength, dBm, dBuV, W, dBuV/m, mW/cm^2, pJ/cm^2, V & VSWR
This RF calculator has been developed by Compliance Engineering as a resource for individuals involved in EMC and RF compliance measurements.
The following table provides conversions for wavelength (from frequency), VSWR (from forward and reflected power) and various other useful conversions.
RF Calculator  

Calculate wavelength for a known frequency (Free Space)  
MHz  λ (m)  


Calculate VSWR from Forward and Reverse Power  
Forward Power (W)  VSWR  
Reverse Power (W)  
Forward Power (dBm)  VSWR  
Reverse Power (dBm)  


Calculate radiated magnetic field from a loop antenna (Low frequency, Close proximity)  
dBuA/m  
Loop Antenna Diameter (m)  pT  
Loop Antenna Windings (N)  dBpT  
Current into Loop Antenna (A)  Tesla  
Distance from Loop Antenna (m)  Guass  
A/m  


Calculate Power Density & Field Level (Far Field)  
Power into Antenna (W)  W/m^2  
Antenna Gain (dBi)  dBuV/m  
Distance from Antenna (m)  V/m  
A/m  
V^2/m^2  
A^2/m^2  
mW/cm^2  


Calculate Power to Generate a Known Field (Far Field)  
Required Field (V/m)  W  
Antenna Gain (dBi)  
Distance from Antenna (m)  


Calculate Circular Waveguide Attenuation  
Frequency (MHz)  dB  
Diameter (mm)  
Length (mm)  


Calculate Gain from Antenna Factor (50 Ω system)  
Antenna Factor (dB/m)  dBi  
Frequency (MHz)  


Convert mW/cm^2 to pJ/cm^2 (Free Space)  
mW/m^2  pJ/cm^2  


Convert pJ/cm^2 to mW/cm^2 (Free Space)  
pJ/cm^2  mW/cm^2  


Convert dBm to W (50 Ω system)  
dBm  W  


Convert W to dBm (50 Ω system)  
W  dBm  


Convert dBm to V (50 Ω system)  
dBm  V  


Convert V to dBm (50 Ω system)  
V  dBm  


Convert dBm to dBuV (50 Ω system)  
dBm  dBuV  


Convert dBuV to dBm (50 Ω system)  
dBuV  dBm  


Calculate Gain from Antenna Factor (50 Ω system)  
Antenna Factor (dB/m)  dBi  
Frequency (MHz) 
Try our other EMC related calculator pages:
 Radiated Power Calculator: Convert between radiated RF power units including: ERP, EIRP, dBuV/m, dBm & mW
 Field Strength Calculator: Convert between various radiated RF field units including: V/m, dBuV/m, dBuA/m, pT, dBpT, Tesla, Guass, A/m, mW/cm^2 & W/m^2