Percentage Calculator Online
Calculate percentages, percentage changes, and percentage of totals.
15% of 200
30
All calculations happen in your browser. No data stored.
What Is a Percentage Calculator?
Percentage Calculator is a free online tool that calculate percentages, percentage changes, and percentage of totals. No files are uploaded — everything is processed locally on your device.
A percentage calculator solves common percentage problems quickly: finding what percent one number is of another, calculating a percentage of a given number, and determining percentage increase or decrease between two values. These calculations come up frequently in school, shopping (discounts and tips), finance (interest rates and returns), and everyday life. Our calculator handles all three types instantly in your browser with no data tracking.
Privacy guarantee: Percentage Calculator processes all files directly in your browser using WebAssembly. No data is uploaded to any server, no information is collected, and the tool works offline after loading. Unlimited usage with no signup, no watermarks, and no file size limits.
How to Use Percentage Calculator
Choose calculation type
Select whether you want to find a percentage, calculate a percentage of a number, or find percentage change.
Enter your values
Input the numbers relevant to your selected calculation type.
Calculate your result
View the percentage result instantly along with the formula used.
Why Use Our Percentage Calculator?
Frequently Asked Questions
How do I calculate what percentage one number is of another?
Divide the part by the whole and multiply by 100. For example, 30 out of 120 is (30 / 120) x 100 = 25%.
How do I calculate a percentage increase between two numbers?
Subtract the old value from the new value, divide by the old value, and multiply by 100. For example, from 50 to 75 is ((75 - 50) / 50) x 100 = 50% increase.
What is the formula for finding a percentage of a number?
Multiply the number by the percentage and divide by 100. For example, 15% of 200 is (200 x 15) / 100 = 30.
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