What is X% of Y?
e.g. What is 20% of 85?
X is what % of Y?
e.g. 17 is what % of 85?
Percent Increase / Decrease
e.g. From $50 to $65 — what % change?
What is the original number?
e.g. 85 is 20% of what number?
How to Calculate Percentages
A percentage is a way of expressing a number as a fraction of 100. The word "percent" literally means "per hundred." To find X% of Y, multiply Y by X and divide by 100. For example, 20% of 85 = (85 × 20) ÷ 100 = 17.
To calculate percent change, subtract the original value from the new value, divide by the original value, and multiply by 100. If the result is positive it's a percent increase; if negative it's a percent decrease.
Percentages are used everywhere — from calculating sales tax and discounts to figuring out tips, grade scores, and interest rates. Our free percentage calculator covers the four most common percentage problems so you can solve any of them in seconds.