Three percentage calculations in one place
Percentages come up everywhere — discounts, exam marks, salary hikes, GST, investment returns. This calculator handles the three questions people ask most. Just type your numbers and the answer updates as you type.
1. What is X% of Y?
Example: a 15% discount on a ₹2,400 jacket is 2,400 × 15 / 100 = ₹360, so you pay ₹2,040.
2. X is what percent of Y?
Example: scoring 72 marks out of 90 is 72 ÷ 90 × 100 = 80%.
3. Percentage increase or decrease
Example: if your monthly salary goes from ₹80,000 to ₹1,00,000, that's (1,00,000 − 80,000) ÷ 80,000 × 100 = 25% hike. A negative result means a decrease.
Common percentage mistakes
- Percent vs. percentage points. If a loan rate moves from 8% to 9%, it rose by 1 percentage point — but by 12.5% in relative terms.
- Successive percentages don't add up. A 20% discount followed by another 10% is a 28% total discount, not 30%.
- Losses need bigger gains to recover. After a 50% fall, you need a 100% gain to get back to where you started.
For business pricing, try the profit margin calculator; for tax on a price, use the GST calculator.
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 2,400 = 2,400 × 15 / 100 = 360.
How do I calculate percentage increase?
Subtract the old value from the new value, divide by the old value and multiply by 100. From 80 to 100: (100 − 80) ÷ 80 × 100 = 25% increase.
How do I find what percentage one number is of another?
Divide the part by the whole and multiply by 100. If you scored 72 out of 90, that's 72 ÷ 90 × 100 = 80%.
Why is a 50% fall followed by a 50% rise not break-even?
Because the percentages apply to different bases. ₹100 falls 50% to ₹50; a 50% rise on ₹50 only brings it back to ₹75. You'd need a 100% rise to recover.
Last updated: 22 September 2026Suggest an improvement · Report a problem