Percentage Change Calculator
Calculate percentage increase, decrease, and change between two values.
How this calculator works
How to use this calculator
Enter the original value and the new value. The calculator shows the percentage increase, decrease, or change between the two numbers.
Formula used
Percentage Change = (New Value − Original Value) ÷ |Original Value| × 100.
Example calculation
If the original value is 80 and the new value is 100, the change is 20. Percentage change is 20 ÷ 80 × 100 = 25%.
What the result means
A positive result means an increase. A negative result means a decrease. A result of 0% means no change.
Frequently asked questions
Why can’t the original value be zero?
Percentage change requires division by the original value, and division by zero is undefined.
Can values be negative?
Yes. The calculator uses the absolute original value in the denominator for clearer change comparison.
Is percentage change the same as percentage difference?
No. Percentage change compares old to new. Percentage difference compares two values relative to their average.