Percentage Formulas
Master percentage calculations with our comprehensive formula reference. From basic percentages to complex percentage changes, find all the mathematical expressions you need.
1Basic Percentage
The fundamental formula to convert a fraction to a percentage.
Example:
Find what percentage 25 is of 100
Variables:
- Part: The portion being measured
- Whole: The total or reference value
- Percentage: Result as a percentage
2Finding X% of a Number
Calculate what a given percentage of a number equals.
Example:
What is 25% of 80?
Variables:
- X: The percentage value
- N: The number
- Result: X% of N
3Percentage Change
Calculate the percentage increase or decrease between two values.
Types of Change:
Percentage Increase:
When New Value > Original Value, result is positive
Percentage Decrease:
When New Value < Original Value, result is negative
Example:
Price changed from $50 to $65
The price increased by 30%
4Finding Original Value
Determine the original value when you know the final value and percentage change.
After Percentage Increase:
Example: Final value is $130 after a 30% increase
After Percentage Decrease:
Example: Final value is $70 after a 30% decrease
5Compound Percentages
Handle multiple percentage changes applied successively.
Multiple Increases:
For consecutive increases of p₁%, p₂%, etc.
Example:
$100 increased by 10%, then by 20%
Note: This is not the same as a 30% increase!
6Percentage Points vs Percentages
Understanding the difference between percentage points and percentage changes.
Percentage Points
Absolute difference between percentages
Difference: 7 - 5 = 2 percentage points
Percentage Change
Relative change between percentages
increase