Percentage Calculator – Calculate Percentages Online Instantly
Percentage Calculator
What is a Percentage Calculator?
A percentage calculator is an online tool that helps you compute percentages quickly and accurately without manual calculation. Percentages are one of the most frequently used mathematical concepts in everyday life — from calculating discounts during shopping, to understanding GST on a bill, to comparing exam scores, to tracking investment returns. This calculator covers all three core percentage problems in one place.
How to Use This Percentage Calculator
- Percentage of a Number: Find what X% of a number equals. Example: What is 15% of 2,500?
- Percentage Increase / Decrease: Find the percentage change between two values. Example: A price went from ₹800 to ₹1,000 — what is the percentage increase?
- What Percentage is X of Y: Find what percentage one number is of another. Example: 45 marks out of 60 — what percentage did you score?
Percentage Formulas with Examples
1. Percentage of a Number
Formula: Result = (Percentage ÷ 100) × Number
Example: What is 18% of ₹5,000?
= (18 ÷ 100) × 5,000 = ₹900
2. Percentage Increase or Decrease
Formula: % Change = ((New Value − Old Value) ÷ Old Value) × 100
Example (Increase): Salary went from ₹30,000 to ₹36,000.
= ((36,000 − 30,000) ÷ 30,000) × 100 = 20% increase
Example (Decrease): Price dropped from ₹1,200 to ₹900.
= ((900 − 1,200) ÷ 1,200) × 100 = −25% (25% decrease)
3. What Percentage is X of Y?
Formula: Percentage = (X ÷ Y) × 100
Example: You scored 78 out of 120 marks.
= (78 ÷ 120) × 100 = 65%
Common Percentage Calculations in Daily Life
| Situation | Calculation Type | Example |
|---|---|---|
| Shopping discount | % of a number | 20% off ₹2,000 = ₹400 discount |
| GST calculation | % of a number | 18% GST on ₹5,000 = ₹900 tax |
| Salary hike | % increase | ₹40,000 to ₹48,000 = 20% hike |
| Exam score | X as % of Y | 85/100 = 85% |
| Investment return | % increase | ₹1,00,000 grew to ₹1,25,000 = 25% return |
| Attendance | X as % of Y | 72 days out of 90 = 80% attendance |
Frequently Asked Questions (FAQs)
How do I calculate percentage of a number?
To find X% of a number, multiply the number by X and divide by 100. For example, 25% of 400 = (25 × 400) ÷ 100 = 100. Use the “Percentage of Number” tab in this calculator for instant results.
How do I calculate percentage increase?
Percentage increase = ((New Value − Old Value) ÷ Old Value) × 100. For example, if a product price rises from ₹500 to ₹600, the increase = ((600 − 500) ÷ 500) × 100 = 20%.
How do I find what percentage X is of Y?
Divide X by Y and multiply by 100. For example, to find what percentage 35 is of 50: (35 ÷ 50) × 100 = 70%. This is useful for calculating exam scores, attendance rates, and conversion rates.
How to calculate discount percentage?
Discount percentage = ((Original Price − Sale Price) ÷ Original Price) × 100. For example, a shirt originally priced at ₹1,200 is on sale for ₹900: discount = ((1,200 − 900) ÷ 1,200) × 100 = 25% off.
How is GST calculated using percentage?
GST is calculated as a percentage of the base price. For example, if a product costs ₹10,000 and GST is 18%: GST amount = (18 ÷ 100) × 10,000 = ₹1,800. Total price with GST = ₹10,000 + ₹1,800 = ₹11,800.
What is the fastest way to calculate 10% of a number?
Move the decimal point one place to the left. For example, 10% of 4,500 = 450. To find 5%, halve the result (225). To find 20%, double the 10% value (900). These shortcuts are useful for quick mental math in everyday situations.