Percentage Calculator

How to Calculate Percentages

What is a Percentage?

A percentage is a way to express a number as a part of a whole, where the whole is represented by 100. The term "percent" comes from "per centum" meaning "by the hundred".

Basic Percentage Formulas

To find X% of a number:
Formula: (X ÷ 100) × Number
Example: What is 15% of 200?
(15 ÷ 100) × 200 = 0.15 × 200 = 30

To find what percent A is of B:
Formula: (A ÷ B) × 100
Example: 30 is what percent of 200?
(30 ÷ 200) × 100 = 0.15 × 100 = 15%

Practical Examples

• Discounts: 25% off ₹800 = (25÷100)×800 = ₹200 off
• Tips: 15% tip on ₹1200 bill = (15÷100)×1200 = ₹180
• Test Scores: 42 correct out of 50 = (42÷50)×100 = 84%
• Tax Calculations: 18% GST on ₹1500 = (18÷100)×1500 = ₹270

Percentage Change Formula

To calculate percentage increase or decrease:
Formula: [(New Value - Old Value) ÷ Old Value] × 100
Example: Price increased from ₹80 to ₹100
[(100-80)÷80]×100 = (20÷80)×100 = 25% increase