Find a percent of a number, what percent one number is of another, or the percentage increase or decrease between two values.
How this calculator arrives at its answer
This percentage calculator handles the three questions people ask most: what is X% of Y, X is what percent of Y, and the percentage change from one number to another. Switch mode, type two numbers, and read the answer.
Percentages turn up everywhere — tips, discounts, grades, taxes and statistics — so having all three modes in one place saves a lot of mental math.
A worked example
As an example, with a percent of 20, of number of 150, the calculator returns a result of 30. Alongside it, Calculation comes out at 20% × 150. Change any field and every figure updates as you type.
Using the calculator
- Pick the mode: “% of number”, “X is what %” or “% change”.
- Enter the two values.
- Read the result instantly.
The formula
% of a number = percent ÷ 100 × number
X is what % of Y = X ÷ Y × 100
% change = (new − old) ÷ old × 100
Common questions
How do I find a percentage of a number?
Divide the percent by 100 and multiply by the number. For example 20% of 150 is 0.20 × 150 = 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 negative result is a decrease.
What is X as a percentage of Y?
Divide X by Y and multiply by 100. For example 30 out of 150 is 30 ÷ 150 × 100 = 20%.