Percentage Error Calculator
Absolute percentage error = |measured − accepted| ÷ |accepted| × 100.
Inputs and units
Enter an experimental value and a nonzero accepted value in the same unit. The accepted value is the reference used in the denominator.
Calculation method
Absolute percentage error = |measured − accepted| ÷ |accepted| × 100.
Worked example
The example values are: Measured value = 98; Accepted value = 100
- Absolute percentage error: 2
- Signed relative error (%): -2
Assumptions and limitations
Check that the inputs and units describe your situation.
Using your result
Calculate after editing the inputs. Copy result saves the displayed values; Download result saves text, and Download CSV creates a spreadsheet-friendly report. Use Print report for a paper copy. Include inputs in copied links only when you want to share them.
Percentage Error Calculator FAQs
Why can error exceed 100%?
An experimental value can differ from the accepted value by more than the accepted magnitude. A zero accepted value has no defined percentage error.