Percentage Change Calculator
Calculate the percentage change between two values to see how much something has increased or decreased.
How it works
What is Percentage Change?
Percentage change measures the relative change between two values, expressed as a percentage. It shows how much a value has increased or decreased compared to its original value.
How to Use the Percentage Change Calculator
Enter the old (original) value and the new value. The calculator will show you the percentage change, indicating whether it's an increase (+) or decrease (-).
Example 1: Price Increase
If a product's price increased from $50 to $65, enter oldValue=50, newValue=65. The percentage change is +30%, meaning the price increased by 30%.
Example 2: Population Decrease
If a city's population decreased from 10,000 to 8,500, enter oldValue=10000, newValue=8500. The percentage change is -15%, meaning the population decreased by 15%.
Example 3: Salary Raise
If your salary increased from $40,000 to $45,000, enter oldValue=40000, newValue=45000. The percentage change is +12.5%, meaning your salary increased by 12.5%.
The Formula
The formula for calculating percentage change is:
Percentage Change = ((New Value - Old Value) / Old Value) × 100
If the result is positive, it's an increase. If negative, it's a decrease.
Common Applications
Percentage change is used in many fields:
- Finance: Track stock prices, investment returns, inflation rates
- Business: Monitor sales growth, revenue changes, profit margins
- Economics: Analyze GDP growth, unemployment rates, price indices
- Science: Measure experimental changes, population growth
- Personal Finance: Calculate salary increases, expense changes
Understanding the Results
A positive percentage change indicates an increase. For example, +25% means the value increased by 25%. A negative percentage change indicates a decrease. For example, -10% means the value decreased by 10%.
Important Notes
The old value cannot be zero, as division by zero is undefined. Both values should be positive numbers for meaningful results. The percentage change can exceed 100% for large increases (e.g., a value doubling would be +100%).