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Percentage calculator
All the common percentage questions in one place.
Quick answer
Pick the question, enter two numbers and read the answer. For example, 15% of 2,400 is 360.
Read the guide: How to calculate percentage: every common case
15% of 2400
360.00
Worked as 15 รท 100 ร 2400.
How it works
"Percent" means "out of 100", so 15% is 15 out of every 100, or 0.15. To find a percentage of a number, multiply by it.
To go the other way, divide the part by the whole and multiply by 100.
Pick the question that matches your problem and the calculator picks the right formula.
The formula
- X% of Y = X รท 100 ร Y
- X is what % of Y = X รท Y ร 100
- X is Y% of what = X รท Y ร 100
- Increase X by Y% = X ร (1 + Y รท 100)
- Decrease X by Y% = X ร (1 โ Y รท 100)
A worked example
15% of 2,400 = 15 รท 100 ร 2,400 = 360. And 360 is 15% of 2,400 because 360 รท 2,400 ร 100 = 15.
Common questions
How do I calculate a percentage of a number?
Divide the percentage by 100 and multiply by the number. 20% of 80 is 0.2 ร 80 = 16.
How do I find what percent one number is of another?
Divide the first by the second and multiply by 100. 30 out of 120 is 30 รท 120 ร 100 = 25%.
How do I add a percentage to a price?
Multiply by 1 plus the percentage as a decimal. Adding 18% to 500 is 500 ร 1.18 = 590.
What is the difference between percent and percentage points?
Going from 10% to 12% is a rise of 2 percentage points, but a 20% increase in the rate itself.