Percentage Calculator
Basic Percentage
Increase/Decrease
Percentage Difference
% of
About Percentages
A percentage is a way to express a number as a fraction of 100. It is denoted using the percent sign (%). Percentages are used to express proportions, changes, and comparisons.
Common Percentage Formulas:
| Calculation | Formula | Example |
|---|---|---|
| What is X% of Y? | (X/100) × Y | 20% of 50 = (20/100) × 50 = 10 |
| X is what % of Y? | (X/Y) × 100 | 10 is (10/50) × 100 = 20% of 50 |
| Percentage increase | [(New - Original)/Original] × 100 | 50 to 60 is [(60-50)/50] × 100 = 20% increase |
| Percentage decrease | [(Original - New)/Original] × 100 | 50 to 40 is [(50-40)/50] × 100 = 20% decrease |
| Percentage difference | [|V1 - V2|/((V1 + V2)/2)] × 100 | Difference between 40 and 50 is [10/45] × 100 = 22.22% |
Common Percentage Conversions:
- To convert fraction to percentage: Multiply by 100 (e.g., 1/4 = 25%)
- To convert decimal to percentage: Multiply by 100 (e.g., 0.75 = 75%)
- To convert percentage to decimal: Divide by 100 (e.g., 45% = 0.45)
Real-World Percentage Applications:
- Calculating discounts and sales tax
- Determining test scores and grades
- Analyzing financial growth or decline
- Comparing statistical data
- Calculating tips at restaurants