Percentage Calculator
Calculate percentages easily
Frequently Asked Questions
How do I calculate a percentage of a number?
Multiply the number by the percentage divided by 100. Result = Number × (Percentage / 100). For example, 25% of 200 = 200 × 0.25 = 50. The calculator handles all percentage operations instantly.
How do I calculate percentage increase or decrease?
Percentage change = ((New - Old) / Old) × 100. Price went from $80 to $100: change = (100-80)/80 × 100 = 25% increase. From $100 to $80: change = (80-100)/100 × 100 = -20% decrease.
How do I find what percentage one number is of another?
Divide the part by the whole and multiply by 100: Percentage = (Part / Whole) × 100. 35 out of 200 = (35/200) × 100 = 17.5%.
How do I calculate the original price before a discount?
Original = Final Price / (1 - Discount Rate). If an item costs $75 after a 25% discount: Original = $75 / (1 - 0.25) = $75 / 0.75 = $100.
Why is a 50% decrease followed by a 50% increase not the same?
Because the base changes. $100 decreased by 50% = $50. Then $50 increased by 50% = $75, not $100. The decrease is calculated on the larger number, while the increase is calculated on the smaller number.