Percentage Calculator

Reverse: Part = (Percentage ÷ 100) × Whole

Percentages appear everywhere in daily life — exam scores, discounts, tax rates, investment returns, and more. Our percentage calculator handles all common percentage problems: finding what percentage one number is of another, calculating a percentage of a number, finding percentage increase or decrease, and working backwards from a percentage to the original value.

Key percentage formulas: (1) What is X% of Y? = Y × X/100. (2) X is what % of Y? = (X/Y) × 100. (3) Percentage increase: (New−Old)/Old × 100. (4) Percentage decrease: (Old−New)/Old × 100. (5) Original value before X% increase: New Value ÷ (1 + X/100). These cover virtually every real-world percentage problem.

Common uses in India: GST calculation (18% of ₹10,000 = ₹1,800), exam mark percentage (450 out of 500 = 90%), salary hike percentage (from ₹50,000 to ₹60,000 = 20% increase), profit percentage (sold ₹1,200, bought ₹1,000 = 20% profit), discount calculation (30% off ₹2,000 = ₹1,400 final price). Our free percentage calculator online handles all of these in seconds.