Percentage Calculator

Calculate percentages, discounts, and percentage changes quickly.

What is X% of Y?

% of

X is what % of Y?

is what % of

Percentage change from X to Y

Add / Remove % from a number

What is a Percentage Calculator?

A percentage calculator is a mathematical tool used to find a percentage of a given number, or to determine what percentage one number is of another. Percentages are a fundamental part of everyday life, used in everything from finance and shopping to science and statistics.

Our calculator provides four different modes to handle all your common percentage-related questions, from calculating simple interest to determining percentage increases or decreases.

How to Use the Percentage Calculator

Choose the module that matches your calculation needs:

Finding a percentage: Use "What is X% of Y?" to find a portion of a total.
Finding a ratio: Use "X is what % of Y?" to see how one value relates to another as a percentage.
Calculating change: Use "Percentage change" to see the relative difference between an old and new value (e.g., growth or decline).
Applying adjustments: Use "Add / Remove %" to calculate values like sales tax, discounts, or tips.

Common Use Cases

Shopping & Retail: Calculate the final price after a discount or determine the amount of sales tax to add.
Finance & Investment: Determine the percentage growth of an investment or calculate interest rates.
Academic & Statistics: Calculate grades, percentages in surveys, or the percentage change in scientific data.
Business Analysis: Analyze profit margins, revenue growth, and cost reductions.

Frequently Asked Questions

How do I calculate a percentage increase?

To calculate a percentage increase, subtract the old value from the new value, divide the result by the old value, and multiply by 100. Our "Percentage change" module does this automatically for you!

How do I calculate a discount?

To find the discount amount, multiply the original price by the discount percentage (as a decimal). For example, a 20% discount on $100 is $20. You can use our "Add / Remove %" module to do this instantly.

Is the calculation accurate?

Yes, our tool uses high-precision mathematical functions to ensure your results are accurate to several decimal places.