Percentage Calculator

Common Percentage Formulas

1. Percentage of a number

Formula: (Percentage / 100) * Number
Example: 20% of 50 = (20/100) * 50 = 10

2. What percentage is X of Y?

Formula: (X / Y) * 100
Example: 10 is what % of 50? = (10/50) * 100 = 20%

3. Percentage Change (Increase/Decrease)

Formula: ((New Value - Old Value) / Old Value) * 100
Example: Price went from $50 to $60. Change = ((60 - 50) / 50) * 100 = 20% increase.