What is a Percentage?
A percentage is simply a fraction out of 100. 25% means 25 out of every 100 — or 25/100, which is 0.25. Percentages let you compare quantities of different sizes on a common scale.
You meet percentages everywhere: discounts on shopping, interest rates on loans, marks in exams, tax rates, and profit margins in business.
Percent of a Number
To find X% of Y, multiply Y by X and divide by 100. For example, 18% of ₹2,500 is 2,500 × 18 ÷ 100 = ₹450.
This is the calculation behind discounts, tips, and tax amounts. If a ₹2,500 item is on 20% discount, you save 2,500 × 20 ÷ 100 = ₹500 and pay ₹2,000.
Percentage Change
Percentage change measures how much a value has increased or decreased: (New Value − Old Value) ÷ Old Value × 100.
If your salary goes from ₹50,000 to ₹55,000, the increase is (55,000 − 50,000) ÷ 50,000 × 100 = 10%. If a stock falls from ₹200 to ₹150, the drop is (150 − 200) ÷ 200 × 100 = −25%.
Reverse Percentages
Sometimes you know the final price after a percentage and need the original. If ₹1,180 is the price after 18% GST, the base price is 1,180 ÷ 1.18 = ₹1,000.
Reverse calculations are where most people make errors. Our Percentage calculator handles all three cases — percent of a number, percentage change, and reverse percentage — instantly and accurately.