Math

Percentage Increase Calculator

Calculate the percentage increase between two numbers. See the formula, each step, and the final result instantly.

Quick Answer

Percentage Increase = ((New Value − Old Value) / Old Value) × 100. For example, going from 50 to 75 is a 50% increase: ((75 − 50) / 50) × 100 = 50%.

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Original Value

New Value

Examples:

Results

Enter two values to calculate the percentage increase.

About This Tool

The Percentage Increase Calculator helps you find the percent change between two numbers. Whether you are tracking price changes, salary raises, investment growth, or comparing data points, this tool gives you an instant, step-by-step breakdown of the calculation.

The Percentage Increase Formula

The formula is straightforward: take the difference between the new and old values, divide by the absolute value of the old number, then multiply by 100. Expressed mathematically: Percentage Increase = ((New − Old) / |Old|) × 100. The absolute value in the denominator ensures consistent results even when working with negative numbers.

When to Use Percentage Increase

Percentage increase is one of the most common calculations in business, finance, and everyday life. Use it to calculate how much a stock price has risen, how much your rent went up, or how your test scores improved over time. It normalizes changes across different scales so you can compare a $5 increase on a $50 item to a $500 increase on a $5,000 item — both are 10%.

Common Mistakes to Avoid

The biggest mistake people make is dividing by the wrong number. Always divide by the original (old) value, not the new value. Dividing by the new value gives you a different metric — percentage difference — which is not the same thing. Another common error is confusing percentage points with percentages. Going from 10% to 15% is a 5 percentage point increase, but a 50% increase.

Negative Results

If the new value is smaller than the old value, the formula returns a negative percentage, indicating a decrease rather than an increase. This calculator handles both cases automatically and labels the result accordingly.

Frequently Asked Questions

How do I calculate percentage increase?

Subtract the old value from the new value, divide the result by the old value, then multiply by 100. For example, from 80 to 100: (100 − 80) / 80 × 100 = 25% increase.

What if the old value is zero?

Percentage increase is undefined when the old value is zero because you cannot divide by zero. In this case you need a different metric, such as absolute change.

Is percentage increase the same as percentage change?

Yes, they use the same formula. Percentage change is the general term that covers both increases (positive result) and decreases (negative result).

How is percentage increase different from percentage points?

Percentage increase is relative. Going from 20% to 25% is a 25% increase but only a 5 percentage point increase. The distinction matters in finance, statistics, and reporting.

Can I calculate percentage increase with negative numbers?

Yes. If you go from −40 to −20, the increase is ((−20) − (−40)) / |−40| × 100 = 50%. The calculator uses the absolute value of the original number in the denominator.

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