Enter the number of true positives, true negatives, and total samples into the calculator to determine the accuracy of a test.

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## Accuracy Formula

The following formula is used to calculate the accuracy of a test.

A = ( TP + TN ) / S

- Where A is the accuracy
- TP is the true positives
- TN is the true negatives
- S is the total number of samples

To calculate the accuracy of a test, sum the true positives and true negatives, then divide by the total number of samples.

## Accuracy Definition

Accuracy is defined as the measure of how many tests it takes to achieve a correct result.

## Accuracy Example

How to calculate accuracy?

**First, determine the number of true positives.**Add up the total number of true positives produced by the test.

**Next, determine the number of true negatives.**Add up the total number of true negatives produced.

**Finally, calculate the accuracy.**Calculate the accuracy by summing the true negatives and positives and then dividing by the total number of samples (total number of tests performed)

## FAQ

**What is accuracy?**

Accuracy is a measure of a test’s ability to achieve the correct result. For example, if a certain test should yield a value of 10, but the actual results in a value of 9, the accuracy is 9/10 = .90 = 90%.

**When is accuracy used?**

Accuracy is most often used in the medical field when analyzing how correct a specific test is.