Percentage Calculator

Introduction

A percentage calculator helps you quickly find percentages of numbers. Whether you need to figure out what 25% of 200 is, find what percent one number is of another, or calculate the percentage change between two values, this tool makes it simple. Percentages show up everywhere — in school, shopping, taxes, tips, and data analysis. Instead of doing the math by hand, you can use this calculator to get accurate answers in seconds. Just enter your numbers, and the tool does the rest for you.

How to Use Our Percentage Calculator

Enter your numbers below to quickly find percentages. This calculator helps you figure out what percent one number is of another, find a percentage of a number, or calculate percentage change.

Find what percent a number is of another: Type in the smaller number and the total number. The calculator will tell you what percentage the first number is of the second. For example, if you want to know what percent 25 is of 200, enter 25 and 200.

Find a percentage of a number: Enter the percentage value and the number you want to calculate it from. For instance, if you need to find 15% of 300, type in 15 as the percent and 300 as the number. The calculator will give you the result right away.

Calculate percentage change: Enter your original number (the starting value) and the new number (the ending value). The calculator will show you the percentage increase or decrease between the two numbers. This is useful for comparing data like price changes, test scores, or population growth. For a dedicated tool focused specifically on this type of calculation, try our Percent Change Calculator.

What Is a Percentage?

A percentage is a way of expressing a number as a part of 100. The word "percent" literally means "per hundred." For example, 50% means 50 out of 100, which is the same as one half. Percentages help us compare numbers, understand data, and make sense of the world around us.

How to Calculate a Percentage

To find a percentage, you divide the part by the whole and then multiply by 100. Here is the basic formula:

Percentage = (Part ÷ Whole) × 100

For example, if you scored 18 out of 20 on a test, you would calculate: (18 ÷ 20) × 100 = 90%. That means you got 90% of the answers right.

Common Uses of Percentages

Percentages show up everywhere in daily life. Here are some common examples:

• Shopping discounts: A 25% off sale means you save 25 cents for every dollar.
• Grades: Test scores are often shown as percentages to measure how well you did.
• Statistics: Percentages are used to summarize survey results, population data, and probability.
• Finance: Interest rates on savings accounts and loans are expressed as percentages. Tools like our Dividend Yield Calculator rely on percentage calculations to express investment returns.
• Sports: Statistics such as on-base percentage and slugging percentage use percentage-based formulas to evaluate player performance.

Percentage Increase and Decrease

Sometimes you need to find how much something has gone up or down. To calculate a percentage change, use this formula:

Percentage Change = ((New Value − Old Value) ÷ Old Value) × 100

If the result is positive, it is a percentage increase. If the result is negative, it is a percentage decrease. For instance, if a price went from $40 to $50, the percentage increase is ((50 − 40) ÷ 40) × 100 = 25%. Our Percent Change Calculator is specifically designed for this type of computation. Additionally, if you're working in a scientific or experimental context, you may want to check out the Percent Error Calculator to measure how far an observed value deviates from an expected value.

Why Percentages Matter in Statistics

In statistics, percentages are one of the most important tools for understanding data. They let us compare groups of different sizes on an equal basis. For example, saying "60% of students passed" is much clearer than saying "312 students passed" when you don't know the total. Percentages make data easier to read, share, and act on. They also form the foundation for more advanced statistical concepts like the rate of change, which measures how quickly a value shifts over time.

Frequently Asked Questions

What is the formula for finding a percentage of a number?

To find a percentage of a number, multiply the number by the percentage and divide by 100. The formula is: Result = (Percentage × Number) ÷ 100. For example, 20% of 150 is (20 × 150) ÷ 100 = 30.

How do I convert a fraction to a percentage?

Divide the top number (numerator) by the bottom number (denominator), then multiply by 100. For example, 3/4 becomes 3 ÷ 4 = 0.75, and 0.75 × 100 = 75%.

How do I convert a percentage to a decimal?

Divide the percentage by 100. For example, 45% becomes 45 ÷ 100 = 0.45. Just move the decimal point two places to the left.

How do I convert a decimal to a percentage?

Multiply the decimal by 100 and add the percent sign. For example, 0.32 × 100 = 32%. Just move the decimal point two places to the right.

Can a percentage be more than 100%?

Yes. A percentage over 100% means something is more than the whole. For example, if you scored 110 out of 100 with bonus points, that is 110%. In percentage change, a value that triples goes up by 200%.

Can a percentage be negative?

A percentage itself is not negative, but percentage change can be negative. A negative percentage change means the value went down. For example, if a price drops from $100 to $80, the percentage change is -20%.

What is the difference between percentage and percentile?

A percentage is a part of 100 — like scoring 85% on a test. A percentile tells you how you rank compared to others. If you are in the 90th percentile, you scored higher than 90% of people. They measure different things.

How do I find what percent one number is of another?

Divide the part by the whole and multiply by 100. The formula is: Percentage = (Part ÷ Whole) × 100. For example, 30 out of 120 is (30 ÷ 120) × 100 = 25%.

How do I calculate a tip using percentages?

Multiply the bill amount by the tip percentage and divide by 100. For a 15% tip on a $60 bill: (15 × 60) ÷ 100 = $9.00. Add that to the bill for your total.

How do I find the original price before a discount?

Divide the sale price by (1 minus the discount as a decimal). For example, if an item costs $60 after a 25% discount: $60 ÷ (1 − 0.25) = $60 ÷ 0.75 = $80. The original price was $80.

What is the difference between percentage change and percentage difference?

Percentage change compares an old value to a new value and shows how much it went up or down. Percentage difference compares two values without treating either as the starting point — you divide by their average instead. Use percentage change when one value comes before the other in time.

How do I add a percentage to a number?

Multiply the number by (1 + the percentage as a decimal). For example, to add 10% to 200: 200 × 1.10 = 220. This works for markups, tax, and tips.

How do I subtract a percentage from a number?

Multiply the number by (1 minus the percentage as a decimal). For example, to subtract 30% from 500: 500 × 0.70 = 350. This works for discounts and reductions.