Calculators
Percentage Calculator
Calculate percentages three ways: find what percentage one number is of another, work out a percentage of a number, or calculate the percentage change between two values. All three modes update live as you type.
About the Percentage Calculator
This tool covers the three percentage problems that come up most often: finding a percentage of a number, finding what percentage one number is of another, and calculating the percentage change between two values. Answers update instantly as you type.
How each mode works
% of a number: Divide the percentage by 100 and multiply by the number. 15% of 200 = (15 ÷ 100) × 200 = 30.
X is what %: Divide the part by the whole and multiply by 100. 30 is what % of 200? (30 ÷ 200) × 100 = 15%.
% change: ((new − old) ÷ |old|) × 100. Positive means an increase, negative means a decrease. Useful for comparing prices, statistics or any two measurements over time.
Frequently asked questions
How do I calculate X% of a number?
Divide the percentage by 100, then multiply by the number. For example, 15% of 200 = (15 ÷ 100) × 200 = 30. Use the "% of a number" mode and enter both values.
How do I find what percentage X is of Y?
Divide X by Y, then multiply by 100. For example, 30 is what percentage of 200? (30 ÷ 200) × 100 = 15%. Switch to the "X is what %" mode.
How is percentage change calculated?
Percentage change = ((new value − old value) ÷ |old value|) × 100. A positive result is an increase; a negative result is a decrease. Use the "% change" mode.