Enter the dielectric constant, the finger width (cm), the finger length (cm), and the number of fingers into the Interdigitated Capacitor Calculator. The calculator will evaluate the Interdigitated Capacitor. 

Interdigitated Capacitor Formula

The following formula is used to calculate the Interdigitated Capacitor. 

C = (E+1) / W * L * (((n-3)*.089)+.10)


  • C is the Interdigitated Capacitor (PF/cm)
  • E is the dielectric constant 
  • W is the finger width (cm) 
  • L is the finger length (cm) 
  • n is the number of fingers

How to Calculate Interdigitated Capacitor?

The following steps outline how to calculate the Interdigitated Capacitor.

  1. First, determine the dielectric constant.
  2. Next, determine the finger width (cm). 
  3. Next, determine the finger length (cm). 
  4. Next, determine the number of fingers.
  5. Next, gather the formula from above = C = (E+1) / W * L * ((n-3)*.089)+.10).
  6. Finally, calculate the Interdigitated Capacitor.
  7. 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.

dielectric constant = 3

finger width (cm) = 4

finger length (cm) = 5

number of fingers = 10

C = (E+1) / W * L * ((n-3)*.089)+.10) =  ?