Percentage Calculator
What is X% of Y?
What is a Percentage Calculator?
A Percentage Calculator is a versatile online tool that helps you solve the three most common percentage problems — finding what X% of a number is, determining what percentage one number is of another, and calculating the percentage change between two values.
Percentages are used everywhere: discounts while shopping, interest rates, exam scores, tax calculations, financial analysis, and more. This calculator makes all those computations instant and error-free.
Three Modes Explained
- X% of Y (Find the value): Use this to find a percentage of a number. Example: What is 15% of 2,500? Answer: 375. Useful for calculating discounts, tips, or interest.
- X is what % of Y (Find the percentage): Use this to express one number as a percentage of another. Example: 75 is what % of 300? Answer: 25%. Useful for exam marks, profit margins, or market share.
- Percentage Change: Use this to find how much a value increased or decreased. Example: Price went from 800 to 1,000 — that's a 25% increase. Essential for tracking growth, inflation, or price changes.
Percentage Formulas
X% of Y = (X / 100) × Y
X as % of Y = (X / Y) × 100
% Change = [(New – Old) / |Old|] × 100
Frequently Asked Questions
How do I calculate 20% of a number?
Multiply the number by 0.20, or divide by 100 and multiply by 20. Example: 20% of 500 = 500 × 0.20 = 100.
What is the formula for percentage increase?
% Increase = [(New Value − Old Value) / Old Value] × 100. If price rose from 200 to 250, the increase is [(250 − 200) / 200] × 100 = 25%.
How do I find what percentage 45 is of 180?
Divide 45 by 180 and multiply by 100: (45/180) × 100 = 25%. So 45 is 25% of 180.
What is the difference between percentage and percentile?
Percentage is a ratio out of 100 (e.g., you scored 80%). Percentile indicates your rank among a group — 80th percentile means you scored higher than 80% of others.