What Is Percentage Increase?
Percentage increase measures how much a quantity has grown relative to its starting value, expressed as parts per hundred (%). Rather than looking only at the raw difference between two numbers, percentage increase normalizes the growth against the original baseline so you can compare changes across different scales—such as comparing a $5 price change on a $20 item (a 25% increase) against a $5 change on a $100 item (a 5% increase).
How Do You Calculate Percentage Increase?
You can calculate percentage increase manually or with a calculator in three straightforward steps:
- Subtract the original value from the new value to find the absolute difference (
Difference = New Value − Original Value). - Divide the difference by the original value to determine the relative change as a decimal (
Decimal = Difference ÷ Original Value). - Multiply the decimal by 100 and attach the percent sign (
%) to express the relative increase per hundred.
How to Use the Calculator
- Enter your starting number in the Original Value field.
- Enter your updated number in the New Value field.
- Press Calculate Percentage Increase (or press Enter on your keyboard).
- Review the percentage increase, absolute difference, and step-by-step arithmetic, or click Copy Result to copy the summary to your clipboard.
Percentage Increase vs. Percentage Change
While both use the same underlying formula—((New Value − Original Value) ÷ Original Value) × 100—percentage increase specifically describes upward growth where the new value exceeds the original value. Percentage change is the general directional metric that encompasses both increases (positive percentages, e.g., +25%) and decreases (negative percentages, e.g., -25%). Note that both are distinct from percentage difference, which divides the absolute difference by the average of the two numbers when neither number is a starting baseline.
What If the New Value Is Smaller?
If the new value is smaller than the original value (for example, Original = 200 and New = 150), subtracting the original value from the new value produces a negative difference (150 − 200 = -50). Dividing by 200 and multiplying by 100 yields -25%. Rather than calling this a positive increase, it should be interpreted as a 25% decrease (or read directly in our Percentage Decrease Calculator).
What If the Original Value Is Zero?
When the original value is 0, percentage increase cannot be calculated using the standard formula because dividing by zero ((New Value − 0) ÷ 0) is mathematically undefined. Any non-zero increase from zero represents an infinite relative multiple of the starting baseline. In financial, scientific, and operational reporting, when a baseline is zero, best practice is to state the absolute unit change (for example, an increase from 0 to 50 units is an absolute increase of 50 units) rather than reporting a percentage.