Percentage Calculator
Calculate percentages, increases, decreases, and reverse percentages with clear formulas and results.
Calculate a specific percentage of a number. For example, 15% of 200.
Find what percentage one number is of another. For example, 30 is what % of 200?
Calculate the percentage increase or decrease between two values.
If a percentage of an unknown number gives a known result, find the original number.
How to use this tool
- Choose a calculation mode using the tabs above: percentage of a number, what percentage one number is of another, percentage change, or finding the original value.
- Enter your values in the input fields.
- Click Calculate to see the result along with the formula used.
- Use Reset to clear the fields and start over.
Frequently asked questions
To find X% of a number Y, use the formula: Result = (X / 100) × Y. For example, 15% of 200 = (15/100) × 200 = 30.
Percentage change = ((New Value − Original Value) / |Original Value|) × 100. A positive result indicates an increase, and a negative result indicates a decrease. Note that percentage change from zero is undefined.
A percentage-point change is the arithmetic difference between two percentage values. For example, going from 10% to 15% is a 5 percentage-point increase. A percentage change would describe this as a 50% increase (since 5 is 50% of 10). This tool calculates percentage change. If you need the percentage-point difference, simply subtract the two percentages.