Percentage Change Calculator
Calculate the percentage increase or decrease between two numbers. Find the exact percent change from an old value to a new value — useful for prices, statistics, performance metrics, and more.
Part of our Math & Percentage Calculators collection.
Percentage Change Calculator
Free online calculator
Results update automatically as you type
How to Use This Calculator
- 1
Enter the original (starting) value.
- 2
Enter the new (ending) value.
- 3
See the percentage change instantly — positive means increase, negative means decrease.
Percentage Change Formula
Percentage Change = ((New Value − Old Value) / |Old Value|) × 100 Positive result = percentage increase Negative result = percentage decrease
Example Calculation
Example: Price went from $80 to $100
Inputs
oldValue: 80newValue: 100
Result
+25% increase
(100 − 80) / 80 × 100 = 25% increase. The price increased by 25%.
Frequently Asked Questions
Why is a 50% decrease not the same as a 50% increase?
A 50% decrease on $100 = $50. A 50% increase on $50 = $75 — not $100. Percentage changes are asymmetric. This is why a stock that drops 50% needs to gain 100% to recover.
What's the difference between percentage change and percentage points?
If interest rates rise from 2% to 3%, that's a 1 percentage point increase but a 50% change. The terms are often confused — percentage points measure absolute change in a rate; percentage change measures relative change.