Percentage Calculator
Calculate percentages easily. Find what percent one number is of another, increase or decrease by a percentage, and more.
What is X% of Y?
What Is the Percentage Calculator?
The percentage calculator helps you solve three common types of percentage problems: finding a percentage of a number, determining what percent one number is of another, and calculating the percentage change between two values. Percentages are used everywhere — from shopping discounts to statistics.
Formula
How to Use
Select the type of calculation you need using the tabs. Enter the required values into the input fields and click Calculate. The result with step-by-step workings will appear below.
Example Calculation
To find 15% of 200: select 'X% of Y', enter 15 and 200. The result is 30. Formula: (15 / 100) × 200 = 0.15 × 200 = 30.
Understanding Percentage
Percentages are one of the most widely used mathematical concepts in daily life. From calculating tips at a restaurant to understanding interest rates on a mortgage, percentages help us express proportions in a standard and intuitive way.
The word "percent" comes from the Latin "per centum," meaning "by the hundred." When we say 25%, we mean 25 out of every 100. This standardization makes it easy to compare different ratios on a common scale.
Our percentage calculator supports three essential operations. The first finds what a given percentage of a number is — useful for discounts, taxes, tips, and commissions. The second determines what percent one number is of another — great for test scores, conversion rates, and ratios. The third calculates the percentage change between two values — essential for financial analysis, growth tracking, and data comparison.
Each calculation includes step-by-step workings so you can understand the process and verify the result. This makes the tool perfect for students learning percentages and professionals who need quick, verifiable calculations.
Frequently Asked Questions
How do I calculate a discount percentage?
Use the "X% of Y" mode. Enter the discount percentage and the original price. The result is the discount amount. Subtract it from the original price to get the sale price.
What is the difference between percentage and percentile?
A percentage is a fraction of 100. A percentile indicates a position in a distribution — for example, the 90th percentile means you scored higher than 90% of all values.
Can percentage change be negative?
Yes. A negative percentage change means a decrease. For example, going from 100 to 80 is a -20% change.
How do I calculate tax on a purchase?
Use "X% of Y" with the tax rate and price. For example, 8.5% of $50 = $4.25. Add it to the price for the total: $54.25.