Percentage Calculator
Three calculators in one — percentages of a number, percentage of a total, and percentage change.
15% of 200 = 30
How to Use This Calculator
This percentage calculator offers three modes to handle any percentage calculation you need. Use the tabs above to switch between modes: calculating a percentage of a number, finding what percentage one number is of another, or determining the percentage change between two values.
Simply enter your numbers in the input fields and the result updates instantly—no need to click a calculate button. Each mode includes a clear explanation below the result showing the formula used.
Common Use Cases
- Shopping discounts: Calculate 20% off £50 to find your savings
- Tips and gratuities: Work out 15% or 18% of your restaurant bill
- Tax calculations: Add VAT (20%) to a base price or remove it from a total
- Exam scores: Convert marks like 45/60 into a percentage grade
- Financial analysis: Calculate percentage growth or decline in revenue, profits, or stock prices
- Survey results: Express proportions as percentages for clearer reporting
Tips & Tricks
Reverse percentage calculations: If you know an item costs £60 after a 25% discount, you can find the original price by calculating what number gives £60 when reduced by 25%.
Percentage points vs percentages: When comparing percentages, remember that moving from 10% to 15% is a 5 percentage point increase, but a 50% relative increase.
Quick mental math: To find 10% of any number, just move the decimal point one place left. For example, 10% of 250 is 25. Then multiply or divide for other percentages.
Frequently Asked Questions
Related Tools
How to calculate a percentage
A percentage represents a fraction of 100. To find X% of a number, multiply the number by X and divide by 100. To express one number as a percentage of another, divide the part by the whole and multiply by 100. Percentage change is the difference between two values divided by the original, times 100.