Math
Percentage Difference Calculator
Find the percentage difference between two values, and the percentage change from one to the other.
Percentage difference
22.22%
- Change from first to second
- 25%
- Difference
- 30
120 and 150 differ by 22.22% of their average. Going from 120 to 150 is a 25% change.
How it's worked out
- Percentage difference
|120 − 150| ÷ ((120 + 150) ÷ 2) × 10022.2222%
- Percentage difference compares two values on an equal footing; percentage change measures from a starting value. Use change when one value came first.
The formula
Percentage difference = |a − b| ÷ ((a + b) ÷ 2) × 100
Worked example
120 and 150: the difference is 30 and the average 135, so they differ by 22.22%. Going from 120 to 150 is a 25% increase.
Questions people ask
How do I calculate percentage difference?
Divide the difference by the average of the two values and multiply by 100. 120 and 150 differ by 30 ÷ 135 = 22.2%.
What's the difference between percentage difference and percentage change?
Change measures from a starting value (120 to 150 is +25%); difference compares two values on an equal footing.
About this calculator
Formula and rules last checked 25 October 2026Written and tested by the CalculatorDex teamReport a problem