Percentage Calculator

Understanding Percentage Calculations

Percentages are fractions of 100 used to express how large or small one quantity is relative to another. Here is how the math works behind the scenes:

• Finding X% of Y: Convert the percentage to a decimal (X / 100) and multiply by Y. (Example: 20% of 50 = 0.20 × 50 = 10)
• Finding what % X is of Y: Divide X by Y, then multiply by 100. (Example: 10 is what % of 50? -> (10 / 50) × 100 = 20%)
• Percentage Increase/Decrease: Subtract the old value from the new value, divide by the old value, and multiply by 100.