Percentage Error Calculator
Use this calculator when one number is an accepted or true value. The formula divides the absolute gap by that accepted value, not by the average of the two measurements.
How this is calculated
Take the absolute difference, divide by the absolute accepted value, then multiply by 100.
|experimental − accepted| / |accepted| × 100
- |9.8 − 10| / 10 × 100 = 2%.
- |48 − 50| / 50 × 100 = 4%.
- The accepted value cannot be zero.
Percentage difference between 9.8 and 10 would use average 9.9 as the base and would not equal 2%. Use difference only when neither value is the standard.
Not the same as
Error has a true value. Difference does not.
- Percentage difference Difference divides by the average of the two numbers. Error divides by the accepted value. Open percentage difference
Related tools
Percentage-error questions
2%. The gap is 0.2, and 0.2 / 10 × 100 = 2.
Because one value is treated as correct. Averaging would be percentage difference.
Yes. Absolute difference removes the sign, so overestimates and underestimates are reported the same way.
The formula cannot run. There is no accepted scale to divide by.
What-percent is part over whole. Error is a gap over an accepted value.