About the Percentage Calculator
Discounts, tips, exam marks, pay rises and price changes all come down to percentages. This calculator answers the most common percentage questions instantly as you type, and shows the formula it used so you can check the working.
How to use the Percentage Calculator
- Pick the calculator that matches your question.
- Type your numbers — the answer updates automatically.
- Click the result to copy it.
Frequently asked questions
How do I calculate a percentage of a number?
Multiply the number by the percentage and divide by 100. For example, 15% of 200 = 200 × 15 ÷ 100 = 30.
How do I calculate percentage increase or decrease?
Subtract the old value from the new value, divide by the old value and multiply by 100. From 50 to 65: (65 − 50) ÷ 50 × 100 = 30% increase.
How do I find what percent X is of Y?
Divide X by Y and multiply by 100. For example, 45 out of 60 = 45 ÷ 60 × 100 = 75%.
How do I work out a sale price?
Multiply the price by (100 − discount) ÷ 100. A 25% discount on 80 is 80 × 0.75 = 60.