Percentage Increase Calculator
The Percentage Increase Calculator finds the percent change between two numbers. Enter the original value and new value; the result updates instantly. Includes the step-by-step formula so you can verify the math.
How It Works
The formula is (new value - original value) / original value × 100. A positive result means increase; negative means decrease. For percentage increase, we show the absolute positive value with "increase" label; for decrease, the absolute positive value with "decrease" label.
Common Uses
Percentage change is used for: year-over-year sales comparisons, measuring performance improvement, calculating investment returns, measuring price inflation, tracking fitness progress, comparing experimental results, and reporting any kind of growth or decline.
Common Mistakes
Be careful about the direction - percentage change is always relative to the ORIGINAL value, not the new one. A change from 100 to 50 is a 50% decrease, not a 100% decrease (that would mean going to zero). A change from 50 to 100 is a 100% increase, not a 50% increase.
Frequently Asked Questions
How do I calculate a percentage?
To find X% of Y: multiply X by Y and divide by 100. Example: 20% of 150 = 20 × 150 ÷ 100 = 30.
How do I calculate percentage change?
Subtract the old value from the new, divide by the old, multiply by 100. Example: change from 80 to 100 = (100-80) ÷ 80 × 100 = 25% increase.
What is the difference between percent of and percent off?
"25% of 100" is 25. "25% off 100" is 75 (the remaining 75%). These are different operations.
Can percentages exceed 100%?
Yes. A percentage increase can be any size. For example, if sales go from 100 to 300, that is a 200% increase.
Do successive percentage increases add up?
No. A 25% increase followed by another 25% increase stacks multiplicatively: 1.25 × 1.25 = 1.5625, which is a 56.25% total increase.
How do I calculate percentage decrease?
Same formula as percentage change, but the result will be negative. We show it as a positive number labeled "decrease".
What is a percentage point vs a percentage?
A percentage point is the arithmetic difference between two percentages. A change from 10% to 15% is 5 percentage points, but a 50% relative increase.
Can I use this for tax, tip, or discount calculations?
Yes - all of these are percentage operations. See our Tip Calculator at /calculator/tip-calculator for specialized tip math.