Percentage Calculator
Calculate percentages, increases, and decreases
Calculator
Calculate what a percentage of a number equals.
What is 15% of 200?
(15% × 200) = 30.00
Quick Formulas
- • X% of Y = (X / 100) × Y
- • What % is A of B = (A / B) × 100
- • % Change = ((New - Old) / Old) × 100
- • Add X% = Value × (1 + X/100)
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Calculate percentages, increases, and decreases
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Percentage Formulas
X% of Y = Y × (X/100) Change% = ((New-Old)/Old) × 100 What % is X of Y = (X/Y) × 100
Percentages are hundredths. 25% = 25/100 = 0.25
Frequently Asked Questions
Multiply the number by the percentage divided by 100. Example: 25% of 80 = 80 × (25/100) = 80 × 0.25 = 20. Alternatively: move decimal two places left (25% = 0.25) then multiply.
Percentage change = ((New - Old) / Old) × 100. If price goes from $50 to $65: (65-50)/50 × 100 = 30% increase. If $50 to $40: (40-50)/50 × 100 = -20% (20% decrease).
Divide the part by the whole, multiply by 100. What percent is 15 of 60? 15/60 × 100 = 25%. This tells you how much of the whole the part represents.
For increase: Original = New / (1 + percentage/100). If price after 20% increase is $120: 120/(1.2) = $100. For decrease: Original = New / (1 - percentage/100).