How to Calculate Percentages
Percentages express a number as a fraction of 100. They are used everywhere from shopping discounts to scientific data.
The Formula
Percentage = (Part / Whole) x 100Where:
PartPart — The portion you are measuringWholeWhole — The total or full amount%Percentage — Result expressed as percentStep-by-Step Example
Here's how to calculate percentages step by step:
- 1Identify values: Determine the part and the whole from your problem.
- 2Divide: Divide the part by the whole to get a decimal.
- 3Multiply by 100: Multiply the decimal by 100 to convert to a percentage.
Following these 3 steps gives you the final percentages value.
Skip the Math
If you scored 45 out of 60 on a test, your percentage is (45/60) x 100 = 75%. This tells you exactly how much of the material you answered correctly.
Use the Free CalculatorWhy You Need This Calculation
- Percentages appear in discounts, taxes, tips, grades, and statistics, making them essential for daily math.
Common Mistakes
Dividing whole by part instead of part by whole.
Always place the part in the numerator.
Forgetting to multiply by 100.
The decimal 0.25 means 25%, not 0.25%.
Confusing percentage increase with total.
A 20% increase on 100 is 120, not 20.