Percent Error Calculator

Percent Error Calculator

Enter the accepted and observed values to calculate the percent error, non-absolute error, and absolute error.

Percent Error Calculator

Our Percent Error Calculator allows you to determine the difference between the accepted (true) value and your measured (observed) value. It provides percent error, absolute error, and signed error values quickly and efficiently.

What is Percent Error?

Percent error measures the difference between the expected value and the value you observed. It helps you assess the accuracy of your results or predictions. For example, if a bag of flour is labeled 5 kg but actually weighs 5.4 kg, the difference is 0.4 kg. Using percent error, the discrepancy is calculated as 4%.

How to Use Our Percent Error Calculator

Enter the accepted (true) value.
Input the measured (observed) value.
Click the “Calculate” button.

Features of This Calculator

Step-by-Step Solution

The calculator provides not only the final percent error but also a detailed step-by-step solution. This is useful for homework, assignments, or verifying manual calculations.
Multiple Results

Along with percent error, the calculator shows absolute error and signed error. You get three outputs at once.
Completely Free

No subscription or payment is required. Use this calculator anytime to quickly compute percent error, absolute error, and signed error values.

Calculator Outputs

Percent error
Absolute error
Signed error
Step-by-step calculation

What is Absolute Error?

Absolute error is the non-negative difference between the true value and the observed value. You can calculate it manually using:

Absolute error = |Vtrue - Vobserved|

Formula for Relative Error

Relative error compares the absolute error to the true value. Use the formula:

Relative error = |Vtrue - Vobserved| / Vtrue

How to Calculate Percent Error by Hand

Manual calculation is simple. Use this formula:

Percent error = |Vtrue - Vobserved| / Vtrue × 100%

References

Wikipedia: Approximation error

Percent Error Calculator