Percentage Error Calculator

Calculate percent error between an experimental value and an accepted value.

Value Details	Enter Value
Experimental Value
Accepted Value

Enter the experimental and accepted values.

How to Use the Percentage Error Calculator

Enter the experimental value and the accepted reference value. The calculator measures the absolute difference relative to the accepted value.

Practical Example

If an experiment gives 98 while the accepted value is 100, percent error is |98 − 100| ÷ 100 × 100 = 2%.

Factors That Affect the Result

The accepted value must be meaningful and nonzero. Measurement precision, rounding, calibration and experimental uncertainty can all influence interpretation of the result.

Frequently Asked Questions

Can percent error be negative?

No. This calculator uses the absolute difference, so percent error is nonnegative.

What if the accepted value is zero?

The standard percentage error formula is undefined because it would require division by zero.

Is a lower percent error always better?

Usually it indicates closer agreement, but acceptable error depends on the measurement context.