Percentage Calculator
Work out a percentage of a number, what percent one number is of another, or the percentage change between two values — with the formula shown for every answer.
Type any value — the result updates as you type.
More percentage calculators
Focused versions of this calculator for one job each.
How to calculate a percentage
A percentage is a fraction of 100. “15%” means 15 parts out of every 100, or 0.15 as a decimal. Almost every percentage question is one of three calculations, and the calculator above has a tab for each.
1. What is X% of a number?
Multiply the number by the percentage and divide by 100.
Example: 15% of 240 = 240 × 15 ÷ 100 = 36.
2. X is what percent of Y?
Divide the part by the whole and multiply by 100.
Example: 36 out of 240 = 36 ÷ 240 × 100 = 15%.
3. Percentage change
Subtract the old value from the new one, divide by the old value and multiply by 100. A positive result is an increase, a negative one a decrease.
Example: from 200 to 260 = (260 − 200) ÷ 200 × 100 = +30%.
Common mistakes
- Dividing by the wrong number. In a percentage change, always divide by the starting value, not the new one.
- Adding percentages in a row. A 10% rise followed by a 10% fall does not bring you back to the start: 100 → 110 → 99.
- Mixing up percent and percentage points. A rate going from 4% to 5% rose by 1 percentage point, which is a 25% increase.
Frequently asked questions
How do I calculate a percentage of a number?
Multiply the number by the percentage and divide by 100. For example, 20% of 80 is 80 × 20 ÷ 100 = 16.
How do I find what percent one number is of another?
Divide the first number by the second and multiply by 100. For example, 12 is 12 ÷ 48 × 100 = 25% of 48.
How do I calculate a percentage increase?
Subtract the original value from the new value, divide by the original value and multiply by 100. From 50 to 65 is (65 − 50) ÷ 50 × 100 = 30%.
Can a percentage be more than 100%?
Yes. 150% of a number is one and a half times that number, and a value that triples has grown by 200%.