How do I calculate 20% of a number?

Multiply the number by 0.20, or use the 'What is X% of Y?' tab and enter 20 and your number.

What is the formula for percentage change?

Percentage change = ((New Value - Old Value) / |Old Value|) × 100. A positive result means an increase; negative means a decrease.

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

Divide the part by the total and multiply by 100. For example, 30 out of 120 is (30 / 120) × 100 = 25%.

How do I add a percentage to a number?

Multiply the original number by (1 + percentage/100). For example, to add 15% to 200, calculate 200 × 1.15 = 230.

How to convert a fraction to a percentage?

Divide the numerator by the denominator and multiply the result by 100. For example, 3/4 becomes (3 / 4) × 100 = 75%.

What's the difference between percentage and percentage points?

Percentage points measure the arithmetic difference between two percentages. Going from 10% to 15% is a 5 percentage point increase, but a 50% relative increase.

Can I calculate a percentage greater than 100%?

Yes. A value can be more than 100% of another — for example, 250 is 125% of 200.

Math

↵ to calculate

Percentage Calculator — Find % of Any Number Instantly

Calculate percentages easily! Find what percent of a number is, see how much something changed, or figure out what percentage one number is of another.

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How to use this calculator

👉 Fill in the boxes below and your answer appears instantly — no maths needed, we do it all for you! 🎉

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In plain English — what does this do?

🍬 Say you have 100 candies. If you eat 20 of them, you ate 20% (20 out of 100). This tool helps you quickly find out ‘what part of a number is something?’ — super easy!

📌 Direct Answer & Summary

A percentage calculator helps you find what percent one number is of another, calculate a percentage of a value, or determine percentage change between two numbers. Percentages express a ratio out of 100 and are used everywhere from discounts and taxes to test scores and statistics.

🔢 Percentage (%)

Type a number like 15 (meaning 15 out of 100)

🎯 of this Value

The total number you want % of

What is Percentage Calculator — Find % of Any Number Instantly?

How to use it

1️⃣ Select the mode that matches your question: 'What is X% of Y?', '% Change', or 'X is what % of Y?'.
2️⃣ Enter the known values into the input fields.
3️⃣ The result updates instantly as you type.
4️⃣ Switch between modes to answer different types of percentage questions without clearing your inputs.

Formula

Percentage of a value: Result = (X / 100) × Y. Percentage change: Change = ((New - Old) / |Old|) × 100. Part as a percent: Percent = (Part / Total) × 100.

💡 See it in action — a real example

To find 15% of 200, enter 15 in the percentage field and 200 in the value field — the result is 30. To find the percentage change from 80 to 100, enter those values in the % Change tab to get +25%.

❓ Common questions

How do I calculate 20% of a number?: Multiply the number by 0.20, or use the 'What is X% of Y?' tab and enter 20 and your number.
What is the formula for percentage change?: Percentage change = ((New Value - Old Value) / |Old Value|) × 100. A positive result means an increase; negative means a decrease.
How do I find what percentage one number is of another?: Divide the part by the total and multiply by 100. For example, 30 out of 120 is (30 / 120) × 100 = 25%.
How do I add a percentage to a number?: Multiply the original number by (1 + percentage/100). For example, to add 15% to 200, calculate 200 × 1.15 = 230.
How to convert a fraction to a percentage?: Divide the numerator by the denominator and multiply the result by 100. For example, 3/4 becomes (3 / 4) × 100 = 75%.
What's the difference between percentage and percentage points?: Percentage points measure the arithmetic difference between two percentages. Going from 10% to 15% is a 5 percentage point increase, but a 50% relative increase.
Can I calculate a percentage greater than 100%?: Yes. A value can be more than 100% of another — for example, 250 is 125% of 200.

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