How to Use the Percentage Calculator
- Pick the type of percentage problem you want to solve.
- Enter the two numbers the calculation needs.
- The answer is computed instantly.
- Switch modes to solve a different percentage question.
The three questions percentages answer
Most percentage problems are one of three types: what is X percent of Y, X is what percent of Y, and what is the percentage change from one number to another. Each has a simple formula, and this calculator handles all of them.
For example, to find a percentage of a number you multiply: 20 percent of 150 is 0.20 times 150, or 30. To find what percent one number is of another, you divide and multiply by 100.
Where percentages trip people up
A common mix-up is percentage points versus percent. Going from 10 percent to 12 percent is a rise of two percentage points, but a 20 percent increase in relative terms. Reports often blur the two.
Another is that a percentage increase followed by the same percentage decrease does not return you to the start: a 50 percent gain then a 50 percent loss leaves you at 75 percent of the original. Knowing these quirks helps you sanity-check any figure.
Frequently Asked Questions
How do I find a percentage of a number?
Multiply the number by the percentage divided by 100. For example, 20% of 150 is 150 × 0.20 = 30.
How do I calculate percentage change?
Subtract the old value from the new value, divide by the old value, then multiply by 100. A rise from 80 to 100 is a 25% increase.
What is 'what percent of' used for?
It answers questions like 'what percent is 30 of 150?', here 30 ÷ 150 × 100 = 20%. Useful for scores, tips and proportions.
Can it handle decimals?
Yes. You can enter decimal values and the calculator returns precise percentage results.