About the Percentage Calculator
Percentages are everywhere: shopping discounts, exam marks, tax, tips, interest rates, salary raises and business growth. The Percentage Calculator solves the six most common percentage questions at once, and every answer updates as you type.
- X% of Y: for example, a 15% tip on 200.
- X is what percent of Y: for example, scoring 30 out of 120 marks.
- Percentage change: growth or decline from an old value to a new one.
- Increase by a percentage: adding tax or a salary raise.
- Decrease by a percentage: sale prices after a discount, including the amount saved.
- Find the whole: if 45 is 30% of a number, what is the number?
How to use the Percentage Calculator
- Find the row that matches your question.
- Type your numbers into the boxes.
- Read the answer instantly on the right.
- Use the other rows for related calculations.
Frequently asked questions
How do I calculate a discount?
Use the "decreased by" row: enter the original price and the discount percentage to see the sale price and how much you save.
What is the formula for percentage change?
((new value − old value) ÷ old value) × 100. A positive result is an increase and a negative result is a decrease.
How do I calculate my exam percentage?
Use the "is what % of" row: enter your marks obtained and the total marks.