Percentage Calculator

Solve common percentage problems: what is X% of Y, X is what % of Y, percentage change, and more.

What is X% of Y?

Percent

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X is what percent of Y?

Value

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Percentage change from X to Y

From

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Features

X is what % of Y?

What is X% of Y?

Increase/decrease by X%

Percentage change

How to Use

1. Pick the type of calculation you need.

2. Fill in the values.

3. The answer appears live.

About this tool

Percentages answer three different questions, and mixing them up is the most common mistake: what is X% of a number, what percentage one number is of another, and how much something changed. This calculator keeps the three side by side and updates as you type. "X% of Y" multiplies Y by X ÷ 100, which is how you work out a discount, a tip or a tax amount. "X is what percent of Y" divides X by Y and multiplies by 100, which is how scores, shares and completion rates are expressed. "Percentage change" compares a new value with the old one — (new − old) ÷ old × 100 — and shows increases with a plus sign and decreases as negative numbers, useful for prices, traffic, salaries and investment returns.

Frequently Asked Questions

How do I calculate a percentage increase or decrease?

Subtract the old value from the new value, divide by the old value, and multiply by 100. From 80 to 100 is (100 − 80) ÷ 80 × 100 = +25%; from 100 to 80 is −20%.

Why is a 50% increase followed by a 50% decrease not back to the start?

The second percentage applies to a different base. 100 increased by 50% is 150, and 50% of 150 is 75, so the result is 75. Percentage changes multiply rather than add.

What is the difference between percent and percentage points?

Percentage points measure the gap between two percentages. An interest rate rising from 2% to 3% is an increase of 1 percentage point, but a 50% increase relative to the original rate.

How do I add or remove VAT or sales tax?

To add 20% tax, multiply the net price by 1.20. To remove it from a gross price, divide by 1.20 rather than subtracting 20%, because the tax was calculated on the smaller net amount.

Why can't I calculate a change from zero?

Percentage change divides by the original value, and division by zero is undefined. Growth from zero is usually described in absolute terms instead, for example "from 0 to 40 users".