Percentage Calculator
Quickly calculate percentages, percentage increase or decrease, and find what percent one number is of another.
What is X% of Y?
Result
30
What percent is X of Y?
Result
15%
Percentage Change
Result
50% Increase
Percentage Formulas
Percentage = (Part ÷ Whole) × 100
Percentages represent a fraction of 100. To find what percent X is of Y, divide X by Y and multiply by 100. To find X% of Y, multiply Y by X and divide by 100. Percentage change is calculated as (New - Old) ÷ Old × 100.
Example Calculation
What is 15% of 200?
15% of 200 = (15 × 200) ÷ 100 = 30
Answer: 30
Understanding Percentages
What is a Percentage?
A percentage is a way of expressing a number as a fraction of 100. The word 'percent' comes from the Latin 'per centum' meaning 'by the hundred.' Percentages are used extensively in finance, statistics, and everyday calculations to compare ratios and proportions.
Common Uses of Percentage Calculations
Percentages are used in calculating discounts during sales, determining tax amounts, computing interest rates on loans and investments, analyzing statistical data, measuring growth rates, and in many other financial and mathematical contexts.
Percentage vs Percentage Points
A percentage point is the simple difference between two percentages, while a percentage change is relative. For example, if an interest rate increases from 5% to 7%, that is a 2 percentage point increase, but a 40% increase in the rate itself.
Frequently Asked Questions
How do I calculate 10% of a number?
Simply divide the number by 10. For example, 10% of 500 = 500 ÷ 10 = 50.
How do I calculate 5% of a number?
First calculate 10% (divide by 10), then divide that result by 2. For example, 5% of 500 = (500 ÷ 10) ÷ 2 = 50 ÷ 2 = 25.
How do I add GST to a price?
Multiply the base price by (1 + GST rate/100). For 18% GST, multiply by 1.18.
How do I calculate percentage from two numbers?
Divide the first number by the second and multiply by 100. For example, 40 out of 200 = (40 ÷ 200) × 100 = 20%.
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