Enter the reflected radiation and the incident radiation into the Reflectance Calculator. The calculator will evaluate the Reflectance. 

Reflectance Formula

The following two example problems outline the steps and information needed to calculate the Reflectance.

R = (RR / IR )^2


  • R is the Reflectance (  )
  • RR is the reflected radiation 
  • IR is the incident radiation 

To calculate reflectance, divide the reflected radiation by the incident radiation, then square the result.

How to Calculate Reflectance?

The following steps outline how to calculate the Reflectance.

  1. First, determine the reflected radiation. 
  2. Next, determine the incident radiation. 
  3. Next, gather the formula from above = R = (RR / IR )^2.
  4. Finally, calculate the Reflectance.
  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 radiation = 30

incident radiation = 50

R = (RR / IR )^2 = ?