Percentage Calculator
Calculate percentages, find what percent one number is of another, and compute percentage increase or decrease.
What is X% of Y?
X is what % of Y?
Percentage change from X to Y
The Three Types of Percentage Calculation
Percentage calculations fall into three categories, each answering a different question. The first is finding a percentage of a number — used for calculating discounts, tax amounts, tips, and commissions. The second is finding what percentage one number represents of another — used for grade calculations and performance metrics. The third is calculating percentage change — used in financial reporting, scientific measurements, and business analytics.
Each calculation has a straightforward formula, but errors are surprisingly common when done mentally, particularly when the numbers are awkward or there is time pressure. Mistaking a 20% discount on a given price or reversing numerator and denominator in a percentage-of calculation are very common mistakes that a calculator eliminates reliably.
Real-World Uses of Percentage Calculations
Percentages appear throughout daily life and professional work. Shoppers calculate discounts to compare sale prices and determine actual savings. Diners calculate tips at restaurants. Students and teachers convert raw scores to percentage grades. Financial analysts track percentage changes in revenue, profit margins, and investment returns to understand trends and make decisions.
Marketers track conversion rates, click-through rates, and engagement rates as percentages of total audience. Nutritionists calculate what percentage of daily calorie intake comes from protein, carbohydrates, and fat. HR departments calculate pay rise percentages to ensure equity across different salary bands. A reliable percentage calculator removes the arithmetic errors that occur when these calculations are done under pressure or with unusual numbers.
How to Use Percentage Calculator
- 1
Choose the type of percentage calculation you need.
- 2
Enter your numbers in the input fields.
- 3
The result calculates automatically as you type.
- 4
Use the percentage change section to find increases or decreases between two values.
Frequently Asked Questions
How do I calculate what percent one number is of another?
Use the "X is what % of Y" calculator. Enter the part (X) and the whole (Y), and the percentage is calculated instantly. For example, 25 is 50% of 50.
How do I calculate a percentage increase?
Use the percentage change calculator. Enter the original value as "From" and the new value as "To". A positive result means an increase, negative means a decrease.
How do I find 20% of a number?
Use the "What is X% of Y" calculator. Enter 20 in the X field and your number in the Y field. The result is 20% of that number.