Percentage Change Calculator
Find the percentage increase or decrease between two values.
Find the percentage increase or decrease between two numbers — prices, scores, followers, anything. Enter the old and new values to see the change and the raw difference.
Formula / method
Examples
+25%
−25%
Increase, decrease and the base
Percentage change measures how much a value has moved relative to where it started: the difference divided by the original value, times 100. The original value is the base, and choosing the right base is what people most often get wrong.
Because the base is the starting number, the same absolute change gives a different percentage depending on direction — a rise from 80 to 100 is a 25% increase, but the fall back from 100 to 80 is a 20% decrease.
Percentage change versus percentage points
When the values are themselves percentages, be careful: moving from a 10% rate to a 15% rate is a 5 percentage-point rise, but a 50% relative increase. Naming which you mean avoids a common and costly confusion.
Where it's used
- Measuring a price increase or decrease between two dates
- Tracking growth in followers, sales, or website traffic month over month
- Expressing an investment gain or loss in percentage terms
- Comparing before-and-after values in an experiment or report
- Working out a raise or pay cut as a percentage
Real-world examples
- A stock rising from $80 to $92, a 15% increase
- Website visitors dropping from 12,000 to 9,000, a 25% decrease
- A salary going from $50,000 to $54,000, an 8% raise
- Gas rising from $3.20 to $3.68 a gallon, a 15% increase
Did you know?
Percentage change and 'percentage points' are different: an interest rate moving from 5% to 10% is a 5 percentage-point rise but a 100% increase, a distinction that often causes confusion in news headlines.
FAQ
What if the old value is zero?
Percentage change is undefined when the starting value is zero, because you cannot divide by zero. Use the absolute difference instead.