Percentage Calculator
Calculate percentages, increases, decreases, and discounts with this simple calculator.
Calculate Percentage of a Number
%
How to Calculate Percentages
X% of Y
To find X% of Y, multiply Y by X and then divide by 100.
Result = (Y × X) ÷ 100X is what percent of Y?
To find what percent X is of Y, divide X by Y and then multiply by 100.
Result = (X ÷ Y) × 100Percentage Increase
To calculate a value increased by X%, multiply the original value by (1 + X/100).
Result = Original × (1 + X/100)Percentage Decrease
To calculate a value decreased by X%, multiply the original value by (1 - X/100).
Result = Original × (1 - X/100)Discount (Percent Off)
To calculate the price after a discount of X%, multiply the original price by (1 - X/100).
Result = Original × (1 - X/100)Common Percentage Examples
Percentage in Real Life
- Sales tax (e.g., 8% tax on $100 = $8 tax)
- Discounts (e.g., 20% off $50 = $10 off, final price $40)
- Tips (e.g., 15% tip on $60 bill = $9 tip)
- Grades (e.g., 85 points out of 100 = 85%)
Financial Applications
- Interest rates (e.g., 5% annual interest on $1000 = $50 per year)
- Profit margins (e.g., 25% margin means $25 profit on $100 sale)
- Investment returns (e.g., 12% annual return on $5000 = $600)
- Inflation (e.g., 3% inflation means $100 is worth $97 next year)
Related Tools
About Percentage Calculations
Common Formulas
- X% of Y: Result = (Y × X) ÷ 100
- X is what % of Y: Result = (X ÷ Y) × 100
- Increase by X%: Result = Original × (1 + X/100)
- Decrease by X%: Result = Original × (1 - X/100)
- Discount: Result = Original × (1 - X/100)
Real-World Applications
- Sales taxes and discounts
- Tips and gratuities
- Interest rates and loan calculations
- Investment returns and growth
- Profit margins and markups
- Nutritional information (% daily values)
- Academic grading and scoring
- Statistical analysis and data interpretation
Frequently Asked Questions
How do I calculate what percent one number is of another?
To find what percent X is of Y, divide X by Y and multiply by 100. For example, to find what percent 25 is of 100: (25 ÷ 100) × 100 = 25%. Use the "What Percent" calculator for this.
How do I calculate a percentage of a number?
To calculate X% of a number, multiply the number by the percentage and divide by 100. For example, 25% of 200 = (200 × 25) ÷ 100 = 50. Use the "Basic Percentage" calculator for this.
What is the difference between percent increase and percent decrease?
Percent increase shows how much a value has grown from its original amount, while percent decrease shows how much it has reduced. Both are calculated as: ((New Value - Original Value) / Original Value) × 100.
How do I calculate discount percentages?
To calculate a discounted price, multiply the original price by the discount percentage, divide by 100, then subtract from the original price. The tool provides both the discount amount and final price.
What is the formula for percent change?
Percent change = ((New Value - Original Value) / Original Value) × 100. A positive result indicates an increase, while a negative result indicates a decrease.
Can I use this calculator for sales tax calculations?
Yes! Use the "Percent Increase" calculator to add sales tax to a price. Enter the base price and the tax rate percentage to get the total price including tax.
How do I calculate tip percentages?
Use the "Basic Percentage" calculator to find the tip amount by entering the bill total and tip percentage. Then add this amount to your bill total for the final amount to pay.
What is the difference between percentage and percentage points?
Percentage is a ratio expressed as parts per hundred, while percentage points refer to the arithmetic difference between two percentages. For example, if something increases from 20% to 25%, that's a 5 percentage point increase.
Can this calculator handle decimal percentages?
Yes, the calculator accepts decimal numbers for both values and percentages. You can enter values like 12.5% or calculate percentages of decimal numbers like 45.75.
How accurate are the percentage calculations?
The calculator provides precise mathematical results. For very long decimal results, numbers are typically rounded to 2-4 decimal places for display, but the underlying calculations maintain full precision.
What are some common uses for percentage calculations?
Common uses include calculating discounts and sales prices, determining tax amounts, calculating tips at restaurants, finding profit margins, analyzing test scores, measuring business growth rates, and computing interest rates.
How do I calculate compound percentage changes?
For compound changes, apply each percentage change sequentially. For example, if a value increases by 10% then decreases by 5%, calculate: Original × 1.10 × 0.95. This tool handles single-step calculations; for compound changes, perform multiple calculations.