Enter the manufactured date and the expiration date into the Shelf Life Calculator. The calculator will evaluate the Shelf Life. 

Shelf Life Formula

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

SL = ED - MD


  • SL is the Shelf Life (dats)
  • MD is the manufactured date 
  • ED is the expiration date 

To calculate Shelf Life, subtract the days between the expiration date and the date of manufacture.

How to Calculate Shelf Life?

The following steps outline how to calculate the Shelf Life.

  1. First, determine the manufactured date. 
  2. Next, determine the expiration date. 
  3. Next, gather the formula from above = SL = ED – MD.
  4. Finally, calculate the Shelf Life.
  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.

manufactured date = 9/20/22

expiration date = 9/20/24

SL = ED – MD = ?