Percentage Error Calculator: Measuring Accuracy

How to Use This Tool

This tool calculates the percentage error between an expected value and a measured value. The calculator shows how far your measurement is from the true value.

1. Enter the expected value in the first box.
2. Enter the measured value in the second box.
3. Click on the Calculate button.
4. The calculator shows the percentage error and a brief explanation.
5. If needed, click the Reset button to start over.

Input Field Details

The first field asks for the actual or expected value. Enter the number you believe is correct.

The second field asks for the measured or observed value. Enter the number you obtained.

Understanding the Output

The result shows the percentage error. It is computed by taking the absolute difference between your values, dividing it by the expected value, and then multiplying by 100.

A result of 0% means your measurement is exactly as expected. A small percentage means the measurement is close to the expected value. A larger percentage shows a higher error.

Special Notes

Please enter valid numbers in both fields. Do not use zero as the expected value because that causes a division error.

The calculator displays the formula with your values after you click Calculate. You see both the error percentage and an interpretation in plain terms.

Common Use Cases

This tool works well for homework. Professionals can use it for quality checks. It also helps in lab experiments and routine measurements.

It is useful for any work that involves comparing two sets of numbers. Try it when your data needs a clear analysis of difference.