Percentage Calculator
Three modes: find percentage of a value, calculate percentage change, or determine what percent X is of Y.
Percentage Calculator – Three Essential Calculation Modes
Percentage calculations appear in everyday life constantly: calculating discounts, tracking investment returns, understanding exam scores, computing tips, analyzing price changes, and more. Our calculator handles all three common percentage scenarios instantly.
Percentage Formulas
Mode 1: % of a Number
(X ÷ 100) × Y e.g. 25% of 200 = 50
Mode 2: % Change
((Y − X) ÷ |X|) × 100 e.g. 80 → 100 = +25%
Mode 3: What % is X of Y?
(X ÷ Y) × 100 e.g. 50 of 200 = 25%
Frequently Asked Questions
How do I calculate what % of a number?
Formula: (Percentage ÷ 100) × Number. Example: 25% of 200 = (25 ÷ 100) × 200 = 50. Use Mode 1 in our calculator.
How do I calculate percentage change?
Formula: ((New Value − Old Value) ÷ |Old Value|) × 100. Example: from 80 to 100 = ((100−80) ÷ 80) × 100 = 25% increase. Use Mode 2.
How do I find what percentage X is of Y?
Formula: (X ÷ Y) × 100. Example: 50 is what % of 200? = (50 ÷ 200) × 100 = 25%. Use Mode 3.
What is the percentage decrease formula?
Same as percentage change: ((New − Old) ÷ Old) × 100. If the result is negative, it's a decrease. Example: from 200 to 150 = ((150−200) ÷ 200) × 100 = −25%.
How is GST percentage calculated?
To find the GST amount on a price: GST Amount = Price × (GST Rate ÷ 100). For a ₹1,000 item with 18% GST: ₹1,000 × 0.18 = ₹180 GST. Total price = ₹1,180. Use our dedicated GST Calculator for full GST breakdowns.