About Percentage Calculator
Our percentage calculator helps you quickly calculate percentages for everyday situations. Whether you need to find discounts, calculate tax amounts, determine grade scores, or analyze business metrics, this tool provides accurate results instantly.
How to Use Each Calculator
- What is X% of Y: Calculate a percentage of a number (e.g., "What is 20% of 500?" = 100)
- X is What Percent of Y: Find what percentage one number is of another (e.g., "50 is what percent of 200?" = 25%)
- Percentage Increase: Calculate the percentage increase from one value to another (e.g., from 100 to 150 = 50% increase)
- Percentage Decrease: Calculate the percentage decrease from one value to another (e.g., from 200 to 150 = 25% decrease)
Common Uses for Percentage Calculations
- Shopping: Calculate discounts, sales tax, and final prices
- Finance: Determine interest rates, investment returns, and profit margins
- Education: Calculate test scores, grades, and GPA
- Business: Analyze growth rates, market share, and KPIs
- Health: Track weight loss, fitness goals, and nutritional values
- Real Estate: Calculate commission, down payments, and price changes
Understanding Percentages
A percentage is a number or ratio expressed as a fraction of 100. The word "percent" comes from the Latin "per centum," meaning "per hundred." Percentages are used to express how large or small one quantity is relative to another quantity.
Percentage Formulas
- Percentage of a number: (Percentage ÷ 100) × Number
- What percent: (Value ÷ Total) × 100
- Percentage increase: ((New Value - Old Value) ÷ Old Value) × 100
- Percentage decrease: ((Old Value - New Value) ÷ Old Value) × 100
Tips for Working with Percentages
- Always identify what the percentage is "of" - the base number
- Remember that percentage increases and decreases are not reciprocal
- Use percentages to compare values fairly across different scales
- Double-check your calculations, especially with money
- Round appropriately for your specific use case