Enter the total number of nonconforming units and the total sample size into the Calculator. The calculator will evaluate the Percent Nonconforming. 

Percent Nonconforming Formula

PNCF = NC / SS * 100


  • PNCF is the Percent Nonconforming (%)
  • NC is the total number of units nonconforming
  • SS is the total sample size

To calculate Percent Nonconforming, divide the total number of units nonconforming by the total sample size, then multiply by 100.

How to Calculate Percent Nonconforming?

The following steps outline how to calculate the Percent Nonconforming.

  1. First, determine the total number of units nonconforming. 
  2. Next, determine the total sample size. 
  3. Next, gather the formula from above = PNCF = NC / SS * 100.
  4. Finally, calculate the Percent Nonconforming.
  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.

total number of units nonconforming = 75

total sample size = 90