Percent Error Calculator
Calculate the percent error between a measured (experimental) value and the accepted true value.
Formula: % error = |measured − true| / |true| × 100
About Percent Error Calculator
Percent Error Calculator is a free online calculator that gives you an instant, accurate result as you type. Calculate the percent error between a measured (experimental) value and the accepted true value.
The calculation uses the standard formula % error = |measured − true| / |true| × 100 and updates live with every change to the inputs. Everything runs client-side in your browser — fast, private, and free to use as often as you like.
Percent error uses the absolute difference, so it is always reported as a positive percentage regardless of direction.
Frequently Asked Questions
Is Percent Error Calculator free to use?
Yes. Percent Error Calculator is completely free, with no sign-up, no downloads, and no usage limits. You can use it as many times as you like on any device with a web browser.
How accurate is this calculator?
The calculator applies the standard formula (% error = |measured − true| / |true| × 100) with full floating-point precision and rounds only the displayed result. For most practical purposes the results are exact.
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