Percentage Calculator
Solve any everyday percentage problem. Switch between three modes — finding a percentage of a number, finding what percent one number is of another, or finding the percentage change between two values.
How to use
- 1
Pick a calculation mode
Choose 'X% of Y', 'X is what % of Y', or '% increase / decrease' based on your question.
- 2
Enter the two values
Fill in both fields — the labels update to match the mode you've selected.
- 3
View the result
The answer updates instantly as you type, with no need to press a button.
Examples
- 20% of 150 → 30
- 30 is what % of 150 → 20%
- Change from 150 to 180 → 20% increase
Frequently asked questions
How do I find X% of Y?
Use the 'X% of Y' mode, enter the percentage as X and the value as Y. The result is (X ÷ 100) × Y. For example, 20% of 150 is 30.
How do I find what percentage one number is of another?
Use the 'X is what % of Y' mode. The result is (X ÷ Y) × 100. For example, 30 is 20% of 150.
How is percentage increase or decrease calculated?
Use the '% increase / decrease' mode with the original value and the new value. The result is ((new − original) ÷ original) × 100, shown as an increase or decrease depending on the sign.
Is my data stored anywhere?
No. All calculations happen locally in your browser. Nothing is sent to a server or saved.