Percentage Calculator

Calculate percentages, percentage change and reverse percentages instantly.

Result

X% of YX is what % of Y% changeReverse %

Percentage (%)

Value (Y)

15% of 240 is: 36

Work out what percentage one number is of another, find a percentage of a value, measure percentage increase or decrease, or recover the original value from a result. Everything updates as you type.

How it works

Pick the question you want to answer and fill in the two numbers.

X% of Y multiplies Y by X ÷ 100.
X is what % of Y divides X by Y and multiplies by 100.
Percentage change uses (new − old) ÷ |old| × 100.
Reverse percentage finds the original value: result ÷ (1 ± X ÷ 100).

Examples

15% of 240 = 36
45 is 18% of 250
From 80 to 100 is a +25% change
A price of 120 after a 20% discount was originally 150

Frequently asked questions

How do I calculate a percentage of a number?

Multiply the number by the percentage and divide by 100. For example 15% of 240 is 240 × 15 ÷ 100 = 36.

How is percentage change calculated?

Subtract the old value from the new value, divide by the old value, then multiply by 100. A positive result is an increase and a negative result is a decrease.

Why can't I calculate change from zero?

Percentage change divides by the starting value, so a starting value of zero has no defined percentage change.