Percentage Calculator
Calculate percentages, percentage increase, percentage decrease, and more with our percentage calculator. Perfect for percentage calculation, percentage change calculator, and percentage difference calculator needs.
Percent Calculation Tool | Discount Calculator | Percentage Finder
Our percentage calculator helps you find percentages, calculate percentage changes, and solve reverse percentage problems instantly.
How to Use the Percentage Calculator
- Choose a calculation type — find a percentage of a number, calculate what percent one number is of another, or find the percentage change between two values.
- Enter your numbers in the input fields provided.
- Click "Calculate" to see the result instantly with a step-by-step explanation.
Understanding Percentages
A percentage is a way of expressing a number as a fraction of 100. The word "percent" literally means "per hundred." Percentages are fundamental in everyday math — from shopping discounts and tax rates to exam scores and investment returns.
Common Percentage Formulas
- What is X% of Y? — Multiply: (X ÷ 100) × Y. Example: 15% of 200 = 0.15 × 200 = 30.
- X is what % of Y? — Divide: (X ÷ Y) × 100. Example: 45 is what % of 180? = (45 ÷ 180) × 100 = 25%.
- Percentage change — ((New − Old) ÷ Old) × 100. Example: Price went from $80 to $100 = ((100 − 80) ÷ 80) × 100 = 25% increase.
Real-World Applications
Percentages appear everywhere: a 20% discount on a $50 item saves $10, a 7% sales tax on $100 adds $7, a 5% annual raise on a $60,000 salary adds $3,000, and a stock that rises from $40 to $48 has gained 20%. Understanding percentages helps you make better financial decisions every day.
Frequently Asked Questions
How do I calculate a percentage of a number?
Divide the percentage by 100, then multiply by the number. For example, 25% of 80: divide 25 by 100 to get 0.25, then multiply by 80 to get 20. Our calculator handles this instantly for any values.
How do I calculate percentage increase or decrease?
Use the formula: ((New Value − Original Value) ÷ Original Value) × 100. A positive result indicates an increase, and a negative result indicates a decrease. For example, going from 150 to 180 is a 20% increase.
How do I find what percent one number is of another?
Divide the part by the whole, then multiply by 100. For example, "30 is what percent of 120?" = (30 ÷ 120) × 100 = 25%. This is useful for calculating exam scores, completion rates, and proportions.