Percentage Change Calculator
Calculate the percentage increase or decrease between two values
How to Use This Calculator
Enter Original Value
Type the starting value or original amount in the first field.
Enter New Value
Type the final value or new amount in the second field.
View Result
The percentage change will be displayed in green (increase) or red (decrease).
Formula
Percentage Change = ((New Value - Old Value) / |Old Value|) × 100
Positive result = Increase | Negative result = Decrease
Example 1: Increase from 50 to 75
Change = ((75 - 50) / 50) × 100
Change = (25 / 50) × 100
Change = 0.5 × 100 = +50% (Increase)
Example 2: Decrease from 100 to 80
Change = ((80 - 100) / 100) × 100
Change = (-20 / 100) × 100
Change = -0.2 × 100 = -20% (Decrease)
Example 3: Double from 25 to 50
Change = ((50 - 25) / 25) × 100
Change = (25 / 25) × 100
Change = 1 × 100 = +100% (Doubled)
About Percentage Change Calculator
The Percentage Change Calculator is a powerful tool for calculating the percent increase or decrease between two values. Whether you're tracking business growth, analyzing stock prices, monitoring weight loss, or comparing sales data, this calculator provides instant, accurate results.
When to Use This Calculator
- Business Growth: Calculate revenue growth, profit margins, or market share changes
- Investment Analysis: Track stock price changes, portfolio performance, or ROI
- Sales Performance: Measure sales increases or decreases over time
- Personal Finance: Monitor salary changes, savings growth, or expense reduction
- Health & Fitness: Track weight loss, muscle gain, or body fat percentage changes
- Academic Performance: Compare test scores or grade improvements
Why Use Our Calculator?
- ✅ Visual Indicators: Green for increases, red for decreases
- ✅ Instant Results: Get percentage change immediately
- ✅ 100% Accurate: Precise calculations every time
- ✅ Easy to Interpret: Clear display of increase or decrease
- ✅ Completely Free: No registration or fees
- ✅ Works Everywhere: Mobile-friendly design
Understanding Percentage Change
Percentage change shows how much a value has increased or decreased relative to its original value. A positive percentage indicates growth or increase, while a negative percentage indicates decline or decrease.
- +50% means the value increased by half of its original amount
- +100% means the value doubled
- -50% means the value decreased by half
- -100% means the value decreased to zero
Real-World Applications
Business: A company's revenue increased from $500,000 to $650,000. The percentage change is +30%, indicating strong growth.
Investing: A stock price dropped from $100 to $85. The percentage change is -15%, showing the decline in value.
Health: Someone lost weight from 200 lbs to 180 lbs. The percentage change is -10%, representing successful weight loss.
Tips for Using Percentage Change
- Always use the original/starting value as the denominator
- Percentage change can exceed 100% (when value more than doubles)
- A -100% change means the value reached zero
- Compare percentage changes across similar time periods for accuracy
- Use absolute values when the direction doesn't matter
Frequently Asked Questions
What's the difference between percentage change and percentage difference?
Percentage change compares a new value to an original value (direction matters). Percentage difference compares two values without considering which is "before" or "after."
Can percentage change exceed 100%?
Yes! If a value more than doubles, the percentage change will exceed 100%. For example, going from 10 to 30 is a +200% change.
What if my original value is negative?
The calculator uses the absolute value of the original number to ensure correct percentage calculation.
Why can't the original value be zero?
Percentage change is calculated by dividing by the original value. Division by zero is undefined in mathematics.
How is this different from percentage increase/decrease calculators?
This calculator does both! It automatically determines whether the change is an increase or decrease and displays it accordingly.