Calculate the percentage error between an experimental (observed) value and a theoretical (accepted) value. Used in science, lab experiments, and quality control.
Percentage error measures how far an experimental value is from the true or accepted theoretical value, expressed as a percentage, key in science and quality control.
Percentage Error equals the absolute difference between Experimental and Theoretical values, divided by the Theoretical value, times 100 percent.
Enter your Experimental Observed Value. Enter the Theoretical Accepted Value. Click Calculate Error. View the percentage error, absolute error, and direction of deviation.
Example 1: Measured gravity of 9.8 against accepted 9.81 gives a percentage error of about 0.102 percent.
Example 2: A measured boiling point of 98 degrees against an accepted 100 degrees gives a 2 percent error.
Example 3: A factory predicting 500 units but producing 470 gives a 6 percent error.
Physics and chemistry lab experiments comparing measured versus accepted constants. Quality control checking manufacturing tolerances. Students validating experimental lab results. Forecasting accuracy checks in business.
What counts as a good percentage error. This depends on context, precise experiments may demand under 1 to 2 percent.
How is this different from percentage difference. Percentage error compares against a known correct value, percentage difference is neutral.
Can percentage error be negative. The formula uses absolute value so it is always reported positive.
Why use the theoretical value as denominator. It gives meaningful scale relative to the expected answer.
What if the theoretical value is zero. The formula becomes undefined due to division by zero.