Enter the reflected power and the forward power into the Calculator. The calculator will evaluate the Standing Wave Ratio. 

Standing Wave Ratio Formula

SWR = (1+SQRT(Pr/Pf)) / (1-SQRT(Pr/Pf))


  • SWR is the Standing Wave Ratio (())
  • Pr is the reflected power
  • Pf is the forward power

How to Calculate Standing Wave Ratio?

The following steps outline how to calculate the Standing Wave Ratio.

  1. First, determine the reflected power. 
  2. Next, determine the forward power. 
  3. Next, gather the formula from above = SWR = (1+SQRT(Pr/Pf)) / (1-SQRT(Pr/Pf)).
  4. Finally, calculate the Standing Wave Ratio.
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge.

reflected power = 35

forward power = 25