This free percentage calculator helps you work out percentages in seconds — exam marks, shopping discounts, tips, tax, price increases and decreases, and more. Instead of struggling with formulas on paper, type in your two numbers and get an accurate answer instantly, right in your browser.
How to use the percentage calculator
- Decide what you want to find: a percentage of a number, what percentage one number is of another, or the percentage increase or decrease between two values.
- Type your first value into the first box (for example, your obtained marks or the original price).
- Type your second value into the second box (for example, the total marks or the discounted price).
- The result appears automatically — no need to press a long series of buttons.
- Use the mode options to switch between “percentage of”, “is what percent of”, and “percentage change” calculations.
- Press reset if you want to start a fresh calculation with new numbers.
What is a percentage?
A percentage is a way of expressing a number as a fraction of 100. The word itself comes from the Latin “per centum”, meaning “by the hundred”. When we say 25%, we mean 25 out of every 100. Percentages are used everywhere in daily life: your exam result is given as a percentage, shop sales advertise percentage discounts, banks describe interest in percentages, and news reports describe price rises and population growth in percentage terms. Because they are built on the same base of 100, percentages make it easy to compare values that come from different totals.
Why use an online percentage calculator?
Working percentages out by hand is slow and easy to get wrong, especially when the numbers are large or have decimals. An online percentage calculator removes the guesswork. Students can check homework answers before submitting. Shoppers can instantly verify whether a “40% off” deal is really as good as it sounds. Teachers can convert raw marks into percentages for a whole class in minutes. Small business owners use percentages for profit margins, sales tax, and discounts. The tool is free, works on any phone or computer, and your numbers are processed on your own device — nothing is uploaded or stored.
Percentage formulas with examples
You do not need these formulas to use the tool, but they help you understand what is happening behind the scenes:
1. Find a percentage of a number: (Percentage ÷ 100) × Number. Example: 20% of 250 = (20 ÷ 100) × 250 = 50.
2. Find what percentage one number is of another: (Part ÷ Total) × 100. Example: you scored 45 out of 60 in a test: (45 ÷ 60) × 100 = 75%.
3. Percentage increase: ((New − Old) ÷ Old) × 100. Example: a price rises from 80 to 100: ((100 − 80) ÷ 80) × 100 = 25% increase.
4. Percentage decrease: ((Old − New) ÷ Old) × 100. Example: a jacket falls from 120 to 90: ((120 − 90) ÷ 120) × 100 = 25% decrease.
5. Discount price: Price − (Price × Discount%). Example: 30% off 200 = 200 − 60 = 140 payable.
Frequently asked questions about percentage calculations
How do I calculate a percentage of a number?
Divide the percentage by 100 and multiply by the number. For example, 15% of 200 is (15 ÷ 100) × 200 = 30. Or simply enter both numbers in the calculator above and read the instant result.
How do I convert marks into a percentage?
Divide your obtained marks by the total marks and multiply by 100. If you scored 378 out of 500, that is (378 ÷ 500) × 100 = 75.6%. This works for any subject, test, or board exam.
What is the difference between percentage increase and percentage points?
A percentage increase measures relative change: going from 40% to 50% is a 25% relative increase. A change in percentage points is the simple difference: 50 − 40 = 10 percentage points. The two are not the same, so be careful in news and finance reports.
Is this percentage calculator really free?
Yes. It is completely free with no sign-up, no watermark, and no daily limit. It runs in your browser, so your numbers stay private on your own device.
Percentages show up in almost every calculation you meet. When you also need totals and averages, try our BMI Calculator for health checks, the Age Calculator for exact ages, or the Unit Converter for measurements. You can browse every utility on the All Tools page or return to the KhiyaleeGFX homepage.
