Calculator Inputs
Formula Used
Percent error: |Measured − Accepted| ÷ |Accepted| × 100
Signed percent error: (Measured − Accepted) ÷ Accepted × 100
Absolute error: |Measured − Accepted|
Relative error: Absolute error ÷ |Accepted|
Accuracy: 100 − Percent error
RMSE: √[Σ(Measured − Accepted)² ÷ n]
Percent error measures distance from a trusted reference. Absolute values prevent negative standard errors. Signed error still shows direction.
How to Use
- Select standard, missing-value, or batch mode.
- Enter the requested values and optional unit.
- Set precision and tolerance when needed.
- Press Calculate to view detailed results.
- Copy, print, or export the report.
Example Data
| Measured | Accepted | Absolute Error | Percent Error | Direction |
|---|---|---|---|---|
| 9.7 | 10 | 0.3 | 3% | Underestimate |
| 52 | 50 | 2 | 4% | Overestimate |
| 100 | 100 | 0 | 0% | Exact match |
Frequently Asked Questions
What is percent error?
Percent error compares a measured value with an accepted value. It expresses the difference as a percentage. Smaller results usually indicate closer agreement.
Why is absolute value used?
Absolute value keeps standard percent error nonnegative. It measures size without considering direction. Signed error separately identifies overestimates and underestimates.
Can percent error exceed 100 percent?
Yes, large differences can exceed one hundred percent. This occurs when error exceeds the accepted magnitude. The result remains mathematically valid.
What happens when accepted value is zero?
Relative and percent error require division by accepted magnitude. Division by zero is undefined. Use absolute error instead for that case.
What is signed percent error?
Signed percent error preserves the difference sign. Positive values often indicate overestimation. Negative values often indicate underestimation.
How is accuracy calculated?
This calculator uses one hundred minus percent error. Accuracy may become negative for extreme errors. Interpret it with suitable context.
What does tolerance status mean?
Tolerance sets the maximum acceptable percent error. Results within tolerance receive a pass. Larger results receive a fail.
What is MAPE?
MAPE means mean absolute percentage error. It averages absolute percentage errors across observations. It supports quick batch comparisons.
What is RMSE?
RMSE is root mean square error. It gives larger errors more influence. Its unit matches the measured values.