Percent Error Calculator

Percent error quantifies the accuracy of a measurement by comparing an experimental value to an accepted (actual) value. The formula is |Experimental - Actual| / |Actual| × 100. A smaller percent error indicates a more accurate measurement, while a larger value suggests significant deviation from the expected result.

Percent error is widely used in science, engineering, and quality control. In chemistry labs, it measures how close an experimental yield is to the theoretical yield. In manufacturing, it assesses product tolerance. In physics, it evaluates the precision of experimental measurements against known constants.

Percent error compares a measured value to a known standard. Percent difference compares two measured values when neither is considered the "correct" one. The formulas differ: percent difference uses the average of the two values as the denominator rather than one accepted value.

To minimize percent error, calibrate instruments before use, take multiple measurements and average them, control environmental variables, and use appropriate precision tools. Systematic errors can be identified and corrected, while random errors are reduced by increasing sample size.