Enter the number of false positives and the number of tests into the False Positive Rate Calculator. The calculator will evaluate the False Positive Rate.

## False Positive Rate Formula

The following two example problems outline the steps and information needed to calculate the False Positive Rate.

FPR = FP / T * 100
• Where FPR is the False Positive Rate (%)
• FR is the number of false positives
• #T is the number of tests

To calculate the false positive rate, divide the number of false positives by the number of tests, then multiply by 100.

## How to Calculate False Positive Rate?

The following example problems outline how to calculate False Positive Rate.

Example Problem #1:

1. First, determine the number of false positives.
• The number of false positives is given as: 50.
2. Next, determine the number of tests.
• The number of tests is provided as: 150.
3. Finally, calculate the False Positive Rate using the equation above:

FPR = FP / #T * 100

The values provided above are inserted into the equation below and computed.

FPR = 50 / 150 * 100 = 33.33 (%)

Example Problem #2:

For this problem, the variables required are provided below:

number of false positives = 60

number of tests = 180