Percentage Calculator
What is X% of Y?
Quick Reference
Common Percentages
10% = 0.10 = 1/10
25% = 0.25 = 1/4
50% = 0.50 = 1/2
75% = 0.75 = 3/4
100% = 1.00 = 1/1
Basic Formulas
X% of Y = (X/100) × Y
Increase = Value × (1 + %/100)
Decrease = Value × (1 - %/100)
Change% = ((New-Old)/Old) × 100
About Percentage Calculator
A comprehensive percentage calculator for all your percentage calculation needs. Calculate percentages, percentage increases and decreases, and percentage changes quickly and accurately.
Calculator Types:
- Basic: Calculate what X% of Y is (e.g., 25% of 200 = 50)
- Increase: Increase a value by a percentage (e.g., 100 + 15% = 115)
- Decrease: Decrease a value by a percentage (e.g., 200 - 20% = 160)
- Change: Calculate percentage change between two values (e.g., 50 to 75 = +50%)
Common Use Cases:
- Calculate discounts and sales prices
- Determine tax amounts
- Calculate tips for restaurants
- Find profit margins and markups
- Track percentage growth or decline
- Calculate grade percentages
- Determine interest rates
Examples:
Shopping Discount:
Item costs $80, 25% off → $80 - 25% = $60
Salary Increase:
Current salary $50,000, 10% raise → $50,000 + 10% = $55,000
Sales Growth:
Sales increased from $100,000 to $125,000 → +25% growth
Tips:
- To convert a percentage to decimal, divide by 100 (e.g., 25% = 0.25)
- To convert decimal to percentage, multiply by 100 (e.g., 0.25 = 25%)
- Percentage increase and decrease are not symmetrical (e.g., +50% then -50% ≠ original value)
- Use positive numbers for increases, the calculator handles the math