How to Calculate a Percentage: A Simple Guide

Calculating percentages is useful for everything from discounts and grades to business calculations. If you want to calculate a percentage quickly, you can use our Basic Percentage Calculator.

What Is a Percentage?

A percentage is a way of expressing a number as a part of 100. The word “percent” means “per hundred.” Percentages are commonly written using the % symbol.

For example, 25% means 25 out of every 100. Percentages are used in everyday situations such as discounts, grades, taxes, interest rates, business profits, and changes in prices.

How to Calculate a Percentage

To calculate what percentage one number is of another, divide the part by the whole and multiply the result by 100.

Percentage Formula

Percentage = (Part ÷ Whole) × 100

For example, if you scored 45 points out of 60:

(45 ÷ 60) × 100 = 75%

So, 45 is 75% of 60.

How to Find a Percentage of a Number

Sometimes you already know the percentage and want to find the corresponding amount.

Use this formula:

Percentage of a Number = (Percentage ÷ 100) × Number

For example, to find 20% of 150:

(20 ÷ 100) × 150 = 30

So, 20% of 150 is 30.

How to Calculate What Percentage One Number Is of Another

To find what percentage one number represents of another, use:

(First Number ÷ Second Number) × 100

For example, suppose you want to know what percentage 30 is of 120:

(30 ÷ 120) × 100 = 25%

Therefore, 30 is 25% of 120.

Percentage Calculation Examples

Here are a few simple examples of common percentage calculations.

Example 1: Finding a Percentage

20 out of 80

(20 ÷ 80) × 100 = 25%

Answer: 25%

Example 2: Finding a Percentage of a Number

15% of 200

(15 ÷ 100) × 200 = 30

Answer: 30

Example 3: Finding the Percentage of a Test Score

You scored 72 points out of 90.

(72 ÷ 90) × 100 = 80%

Answer: 80%

Common Types of Percentage Calculations

Percentages are used for many different types of calculations. The formula you use depends on what you are trying to find.

Percentage Increase

Percentage increase shows how much a value has increased compared with its original value.

Percentage Increase = ((New Value − Original Value) ÷ Original Value) × 100

You can use our Percentage Increase Calculator to calculate this quickly.

Percentage Decrease

Percentage decrease shows how much a value has decreased compared with its original value.

Percentage Decrease = ((Original Value − New Value) ÷ Original Value) × 100

Our Percentage Decrease Calculator can calculate the result for you.

Percentage Discount

A percentage discount tells you how much is removed from the original price.

For example, a 20% discount on a $100 item is:

$100 × 20% = $20

The discounted price is:

$100 − $20 = $80

You can use our Percentage Discount Calculator to calculate discounts quickly.

Percentage Difference

Percentage difference is commonly used to compare two values without treating either value as the original or reference value.

Our Percentage Difference Calculator can help you calculate the difference between two numbers.

How to Calculate Percentages Quickly

For simple calculations, you can use the formulas above. However, calculating percentages manually can become time-consuming when the numbers are more complicated.

Our Basic Percentage Calculator lets you enter your numbers and get the result instantly without doing the calculation by hand.

It can be useful for everyday calculations involving prices, grades, discounts, percentages, and other numerical problems.

Why Are Percentages Important?

Percentages make it easier to compare numbers and understand proportions.

They are commonly used in:

• Shopping: discounts, sales, and price changes
• Education: test scores and grades
• Finance: interest rates, returns, and fees
• Business: profits, margins, and changes in revenue
• Taxes: tax rates and amounts
• Statistics: proportions and comparisons
• Everyday life: tips, savings, and budgeting

Understanding basic percentages can make many everyday calculations easier.