How to use this calculator
- Enter or choose original value.
- Enter or choose new value.
- The percentage change updates as you type. Use Copy result or Share to keep it.
Formula
Change % = (New − Original) ÷ |Original| × 100
- Original
- the starting value
- New
- the later value
Worked example
- Difference = 65 − 50 = 15.
- Change = 15 ÷ 50 × 100 = 30%.
Going from 50 to 65 is a 30% increase.
What the result means
Increases and decreases are not symmetric: a 50% fall followed by a 50% rise leaves you at 75% of the start. Going from 80 to 60 is −25%, but going back from 60 to 80 is +33.3%.
Assumptions and limits
- When the original value is negative, change is measured relative to its size, so moving from −50 to −25 is reported as +50%.
- Change from 0 is undefined. Report the absolute difference instead.
Questions
What is the difference between percentage change and percentage points?
If an interest rate goes from 4% to 5%, it rose by 1 percentage point, but by 25% in relative terms.
How do I calculate a percentage decrease?
Use the same formula. A negative result is a decrease: from 80 to 60 is (60 − 80) ÷ 80 × 100 = −25%.