Enter the number of teeth in contact and the total number of teeth into the Contact Ratio Calculator. The calculator will evaluate and display the Contact Ratio. 

Contact Ratio Formula

The following formula is used to calculate the Contact Ratio. 

CR = TC / T
  • Where CR is the Contact Ratio
  • #TC is the number of teeth in contact 
  • #T is the total number of teeth 

To calculate the contact ratio, divide the number of teeth in contact by the total number of teeth.

How to Calculate Contact Ratio?

The following example problems outline how to calculate Contact Ratio.

Example Problem #1:

  1. First, determine the number of teeth in contact.
    • The number of teeth in contact is given as: 45.
  2. Next, determine the total number of teeth.
    • The total number of teeth is provided as: 100.
  3. Finally, calculate the Contact Ratio using the equation above: 

CR = #TC / #T * 100

The values given above are inserted into the equation below and the solution is calculated:

CR = 45 / 100 * 100 = 45.00 (%)


Example Problem #2: 

For this problem, the variables required are provided below:

number of teeth in contact = 60

total number of teeth = 750

Test your knowledge using the equation and check your answer with the calculator above.

CR = #TC / #T * 100 = ?