Financial Tool

Percentage Change

Calculate the percent increase or decrease between two values.

Σ The Formula

% Change = ((New Value - Old Value) / |Old Value|) × 100

Real World Examples

Stock Price Increase
Stock from $50 to $75: ((75-50)/50) × 100 = +50% increase
Weight Loss
Weight from 200 lbs to 180 lbs: ((180-200)/200) × 100 = -10% decrease
Sales Growth
Revenue from $100k to $150k: ((150-100)/100) × 100 = +50% growth
Population Decline
Population from 5000 to 4500: ((4500-5000)/5000) × 100 = -10% decline

# About This Calculator

Percentage change is a mathematical concept used to express how much a value has increased or decreased relative to its original value. It's expressed as a percentage, making it easy to understand proportional changes regardless of the absolute numbers involved.

This metric is crucial in business analytics (tracking sales growth, profit margins), finance (stock price movements, portfolio performance), economics (inflation rates, GDP growth), and science (experimental error analysis, population studies). Understanding percentage change helps you compare growth rates across different scales and time periods.

The formula divides the absolute change by the original value and multiplies by 100. A positive result indicates growth or increase, while a negative result shows decline or decrease. For example, a stock price increasing from $50 to $75 represents a 50% increase, while dropping from $100 to $80 is a 20% decrease.

This calculator automatically handles the sign (positive/negative) and provides clear indication of whether the change represents an increase or decrease, eliminating common calculation errors and making trend analysis straightforward.

How To Use

  1. Enter the Old Value (Start).
  2. Enter the New Value (End).
  3. Click Calculate Difference.

Frequently Asked Questions

Can percentage change be negative?+

Yes! If the new value is smaller than the old value, the result will be negative, indicating a decrease. For example, going from 100 to 80 is a -20% change.

What if the old value is 0?+

You cannot calculate percentage change from zero because division by zero is undefined. If starting from zero, any increase is technically infinite. In such cases, use absolute change instead.

What's the difference between percentage change and percentage point change?+

Percentage change is relative (e.g., interest rate from 2% to 3% is a 50% increase), while percentage point change is absolute (same example is a 1 percentage point increase). Always clarify which you mean!

How do I calculate reverse percentage change?+

If something increased by X%, to find the original value, divide the new value by (1 + X/100). For a decrease, divide by (1 - X/100). For example, if $120 is after a 20% increase, original = 120 / 1.20 = $100.

Why doesn't a 50% increase followed by a 50% decrease return to the original?+

Because each percentage applies to a different base. Starting at 100: +50% gives 150, then -50% of 150 gives 75, not 100. The second percentage operates on the new, larger base.

Is Percentage Change free to use?+

Yes, Percentage Change on Matheric is completely free to use. We believe in accessible education and utility for everyone.

About

Percentage change is a mathematical concept used to express how much a value has increased or decreased relative to its original value. It's expressed as a percentage, making it easy to understand proportional changes regardless of the absolute numbers involved.

This metric is crucial in business analytics (tracking sales growth, profit margins), finance (stock price movements, portfolio performance), economics (inflation rates, GDP growth), and science (experimental error analysis, population studies). Understanding percentage change helps you compare growth rates across different scales and time periods.

The formula divides the absolute change by the original value and multiplies by 100. A positive result indicates growth or increase, while a negative result shows decline or decrease. For example, a stock price increasing from $50 to $75 represents a 50% increase, while dropping from $100 to $80 is a 20% decrease.

This calculator automatically handles the sign (positive/negative) and provides clear indication of whether the change represents an increase or decrease, eliminating common calculation errors and making trend analysis straightforward.

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