Enter the total inspiratory time and the total expiratory time into the I:E Ratio Calculator. The calculator will evaluate and display the I:E Ratio. 

I:E Ratio Formula

The following formula is used to calculate the I:E Ratio.

IE = IT / ET
  • Where IE is the I:E Ratio
  • IT is the total inspiratory time 
  • ET is the total expiratory time 

To calculate an I E ratio, divide the total inspiratory time by the total expiratory time.

How to Calculate I:E Ratio?

The following example problems outline how to calculate I:E Ratio.

Example Problem #1:

  1. First, determine the total inspiratory time.
    • The total inspiratory time is given as: 2.
  2. Next, determine the total expiratory time.
    • The total expiratory time is provided as: 4.
  3. Finally, calculate the I:E Ratio using the equation above: 

IE = IT / ET

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

IE = 2 / 4 = .5


Example Problem #2: 

For this problem, the variables required are provided below:

total inspiratory time = 5

total expiratory time = 6

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

IE = IT / ET = ?