Percentage Calculator
Three common percentage questions in one place — each with the working shown.
The three formulas
Percent of a number: result = number × (percent ÷ 100). So 15% of 200 = 0.15 × 200 = 30.
X is what percent of Y: percent = (X ÷ Y) × 100. So 30 is (30 ÷ 200) × 100 = 15% of 200.
Percentage change: change = ((new − old) ÷ old) × 100. A positive answer is an increase, a negative one is a decrease.
FAQ
How do I find a percentage of a number?
Divide the percentage by 100 and multiply by the number. For example, 15% of 200 is 0.15 × 200 = 30.
How is percentage change calculated?
Subtract the old value from the new value, divide by the old value, and multiply by 100. Positive means an increase; negative means a decrease.
What's the difference between percent and percentage points?
Going from 10% to 15% is a rise of 5 percentage points, but a 50% increase in relative terms. This tool reports the relative percentage change.