Percent Error Calculator
Measured vs. accepted valueRuns locally · nothing uploaded
Percent error
0.9174%
Absolute error
0.09
Relative error
0.009174
|9.72 − 9.81| ÷ |9.81| × 100%
How it works
When to use it
- Compare an experimental value with the accepted value in a lab report.
- Check the accuracy of an instrument or estimate.
Formula
Absolute error = |measured − actual|Percent error = |measured − actual| ÷ |actual| × 100%Worked example
Given: Measured g = 9.72 m/s², accepted 9.81 m/s²
- Absolute error = 0.09.
- Percent error = 0.09 ÷ 9.81 × 100% ≈ 0.917%.
Result: About 0.92% error; the measurement is low.
Reading the result
- Percent error measures accuracy; the spread of repeated measurements measures precision.
Limitations
- Undefined when the actual value is 0.
- To compare two measurements with no accepted value, use percent difference instead.
How to use
- 1Enter the measured (experimental) value.
- 2Enter the accepted (theoretical) value.
- 3Read the absolute, relative and percent error.
FAQ
What is the percent error formula?
Percent error = |measured − accepted| ÷ |accepted| × 100%.
Absolute vs relative error?
Absolute error has units; relative error divides by the accepted value and is unitless.