Percent Change Calculator
Calculate the percentage change between two values. See the formula, direction of change, and absolute difference instantly.
Frequently Asked Questions
What is the percent change formula?
Percent change = ((New Value − Old Value) / |Old Value|) × 100. A positive result means an increase; negative means a decrease.
Why does the formula use absolute value?
The absolute value of the old value is used in the denominator so the formula works correctly even when the old value is negative. This ensures the direction of change is always meaningful.
What if the old value is zero?
Percent change is undefined when the starting value is zero because division by zero is not possible. The tool will show an error in this case.