Percentage Calculator
Calculate percentages instantly: find X% of Y, what percent X is of Y, or the percentage increase/decrease between two numbers.
How It Works
This calculator supports three common percentage operations:
- X% of Y — Multiplies Y by X/100 to find the part.
- What % is X of Y? — Divides X by Y and multiplies by 100 to find the percentage.
- % Increase/Decrease — Calculates the relative change between an original and new value using the formula: ((new − original) / original) × 100.
Frequently Asked Questions
How do I calculate a percentage of a number?
To find X% of Y, multiply Y by X and divide by 100. For example, 25% of 200 is (200 × 25) / 100 = 50.
How do I find what percentage one number is of another?
Divide the part by the whole and multiply by 100. For example, 30 is (30 / 120) × 100 = 25% of 120.
How do I calculate percentage increase or decrease?
Subtract the original value from the new value, divide the result by the original value, and multiply by 100. A change from 80 to 100 is ((100 - 80) / 80) × 100 = 25% increase.