Percent Error Calculator
Calculate percent error between experimental lab measurements and true theoretical values with step-by-step arithmetic.
Percent error
Percent error formula
Percent error compares the absolute discrepancy between an experimental measurement and the known reference:
The theoretical baseline is placed in the denominator to reflect true accuracy.
Frequently asked questions
What is percent error?
Percent error measures the accuracy of an experimental observation compared against an accepted true, known, or theoretical standard. Formula: Percent Error (%) = (|Experimental − Theoretical| ÷ |Theoretical|) × 100.
Can percent error be negative?
In standard scientific and engineering conventions, percent error uses the absolute difference |Experimental − Theoretical|, meaning it is always reported as a positive percentage indicating the magnitude of inaccuracy.
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