Percent Error Calculator
Calculate the percent error between an observed and true value.
About this Tool
The Percent Error Calculator measures the difference between an experimental or observed value and a true or accepted value, expressed as a percentage. It is a common way to evaluate the accuracy of a measurement in science and engineering.
Common Use Cases
Scientific Experiments
Determine the accuracy of your measurements in a chemistry or physics lab compared to theoretical values.
Engineering
Assess the precision of a manufactured part against its design specifications.
Statistics
Evaluate the error of a statistical estimate compared to a known population parameter.
Pro Tips
- !
Absolute Value
Percent error is always a positive value because it measures the magnitude of the error, not its direction.
- !
Context is Key
A 'good' percent error is relative. In some fields, a 5% error is acceptable, while in high-precision engineering, it might need to be less than 0.1%.
- !
Identify Error Sources
A high percent error can indicate issues with your measurement technique, equipment, or experimental setup.