Find X% of a number, what percent one number is of another, and percentage increase or decrease.
What is X% of Y?
A is what percent of B?
Percentage increase / decrease
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How to use the Percentage Calculator
- Pick the calculation you need from the three cards below.
- Type your numbers — the result updates instantly as you type.
- Use the formula shown under each result to check the math or reuse it yourself.
About this tool
Percentages show up everywhere: discounts, tax, tips, exam scores, interest rates and statistics. This calculator handles the three questions people ask most often and shows the formula behind each answer so you can learn it, not just copy it.
The three formulas:
- X% of Y = Y × X ÷ 100
- A is what % of B = A ÷ B × 100
- Change from A to B = (B − A) ÷ A × 100
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 200 is 200 × 15 ÷ 100 = 30.
How do I work out the percentage increase between two numbers?
Subtract the old value from the new value, divide by the old value, then multiply by 100. Going from 50 to 65 is (65 − 50) ÷ 50 × 100 = 30% increase.
What is the difference between percentage points and percent?
Percentage points are the simple difference between two percentages (from 10% to 15% is 5 percentage points). Percent change compares them relatively (from 10% to 15% is a 50% increase).
Can I use negative numbers?
Yes. Negative results show a decrease. For example, going from 80 to 60 gives −25%.