What is the formula for calculating percent error?

# AutoCalculator.org

Percent Error Formula
Measured Value
Exact Value
Percent error
Example: The 1/4 mile trap speed recorded during a trial was 70.0 miles per hour (the measured value).
Later the speedo was calibrated, and it was found that the actual speed reading should have been 69.74 miles per hour (the actual value).
The percentage error in the 1/4 mile trap speed would therefore be 0.37%.