Percentage Calculator
Quickly calculate percentages, find what percentage one number is of another, and work out percentage increases or decreases.
What is X% of Y?
Example: What is 15% of 200?
X is what % of Y?
Example: 30 is what percent of 120?
Percentage Increase / Decrease
Compare an old value with a new value to see the percentage change.
How to calculate a percentage
- X% of Y: multiply Y by X ÷ 100.
- X is what % of Y: divide X by Y and multiply by 100.
- Percentage change: divide the difference by the original value, then multiply by 100.
Useful for
Discounts, price changes, exam scores, business growth, commissions, taxes, budgeting and everyday calculations.
Privacy: Calculations happen entirely in your browser.
Features and Common Use Cases
Use this calculator for everyday percentage problems such as finding a percentage of a number, comparing changes, checking discounts or working with simple business and study calculations. It is designed for quick answers without a spreadsheet.
Frequently Asked Questions
What can the Percentage Calculator do?
It calculates X% of Y, finds what percent X is of Y, and works out percentage increase or decrease.
How do I calculate X% of Y?
Enter the percentage and the number, then click "Calculate". For example, to find 15% of 200, enter 15 and 200.
How do I find what percent one number is of another?
Enter the part and the whole, then click "Calculate". For example, to see what percent 30 is of 120, enter 30 and 120.
How is percentage increase or decrease calculated?
Enter the old and new values, then click "Calculate Change". The formula is ((new - old) / old) x 100.
Are my calculations sent to a server?
No. Calculations happen entirely in your browser.
Is the Percentage Calculator free to use?
Yes, it is free to use.