A percentage calculator lets you solve the three most common percentage problems instantly.
How to use the calculator:
Choose one of the three calculation modes:
- What is X% of Y? — Find a percentage of a number (e.g., What is 15% of 200?)
- X is what % of Y? — Find what percentage one number is of another (e.g., 30 is what % of 200?)
- % change from X to Y — Find the percentage increase or decrease between two values (e.g., from 50 to 75)
Enter your values and the result is calculated instantly.
Formulas
What is X% of Y?
Result = (X / 100) × Y
X is what % of Y?
Percentage = (X / Y) × 100
Percentage change from X to Y:
Change (%) = ((Y − X) / |X|) × 100
A positive result means an increase; a negative result means a decrease.
Examples
Example 1: What is 15% of 200?
Result = (15 / 100) × 200 = 30
Example 2: 30 is what % of 200?
Percentage = (30 / 200) × 100 = 15%
Example 3: Percentage change from 50 to 75?
Change = ((75 − 50) / 50) × 100 = 50% increase
Example 4: Percentage change from 100 to 80?
Change = ((80 − 100) / 100) × 100 = −20% (decrease)
Key features include:
- Three calculation modes in one tool
- Instant results with no button press required
- Supports decimals and negative numbers
- Covers the most common percentage use cases
- Works on desktop, tablet, and mobile