How do I find what X% of Y is?

Multiply Y by X and divide by 100. For example, 20% of 150 is 150 x 20 / 100 = 30. The tool does this instantly.

How do I find what percent one number is of another?

Divide the first number by the second and multiply by 100. For example, 30 out of 150 is 30 / 150 x 100 = 20%.

Yes. You can enter decimal values and the results are shown with sensible precision.

Math Calculators

Work out percentages and ratios quickly.

Free browser toolRuns in your browserNo sign-up

What is X% of Y?

% of

= -

Formula: (X / 100) x Y

X is what percent of Y?

Formula: (X / Y) x 100

Percentage change from X to Y

Formula: ((Y - X) / |X|) x 100. The original value X cannot be zero.

Answer the most common percentage questions instantly: what X% of Y is, and what percent X is of Y.

Handy for discounts, tips, tax, grades and everyday quick math.

Both answers update live as you type, so you can compare figures quickly without opening a calculator app.

Percentage of a number

Input: 15% of 500

Output: 75

15% is 0.15, and 0.15 x 500 is 75.

Percentage change

Input: From 200 to 250

Output: 25% increase

The 50 rise is divided by the original 200 to get 25%.

How do I find what X% of Y is?: Multiply Y by X and divide by 100. For example, 20% of 150 is 150 x 20 / 100 = 30. The tool does this instantly.
How do I find what percent one number is of another?: Divide the first number by the second and multiply by 100. For example, 30 out of 150 is 30 / 150 x 100 = 20%.
Can it handle decimals?: Yes. You can enter decimal values and the results are shown with sensible precision.

Open a related tool to prepare your files or refine the finished result.