Percentage Change Calculator
Calculate the percentage increase or decrease between two values. Useful for tracking price changes, growth rates, score improvements, and financial analysis.
How to Use This Percentage Change Calculator
Follow these simple steps to calculate the percentage change:
- Enter the old (original) value in the first field.
- Enter the new (final) value in the second field.
- Click the "Calculate" button.
- Review the percentage change, direction (increase/decrease), and absolute difference.
Percentage Change Formula
The percentage change between an old value and a new value is calculated as:
Percentage Increase (positive result):
Percentage Decrease (negative result):
Examples
A product price went from $50 to $75:
% Change = [(75 - 50) / 50] × 100 = 50% increase
A test score dropped from 92 to 85:
% Change = [(85 - 92) / 92] × 100 = -7.61% (7.61% decrease)
A city population grew from 200,000 to 250,000:
% Change = [(250000 - 200000) / 200000] × 100 = 25% increase
Frequently Asked Questions
What is the formula for percentage change?
The formula for percentage change is: [(New Value - Old Value) / |Old Value|] × 100%. A positive result indicates an increase, while a negative result indicates a decrease. The absolute value of the old value is used in the denominator to ensure the direction is correctly captured by the sign.
How do you calculate a percentage increase?
To calculate a percentage increase: (1) Subtract the old value from the new value. (2) Divide the result by the old value. (3) Multiply by 100. For example, if a salary goes from $50,000 to $55,000: increase = (55000 - 50000) / 50000 × 100 = 10% increase.
How do you calculate a percentage decrease?
To calculate a percentage decrease: (1) Subtract the new value from the old value. (2) Divide the result by the old value. (3) Multiply by 100. For example, if a stock drops from $200 to $150: decrease = (200 - 150) / 200 × 100 = 25% decrease.
Can percentage change be more than 100%?
Yes. If a value triples (e.g., from 10 to 30), the percentage change is 200%. There is no upper limit. However, percentage decrease is bounded at -100% (the value drops to zero) in standard scenarios, though mathematically the formula can produce values below -100% if the new value is negative.