Percentage Calculator
Easily calculate percentages, increases, and decreases.
Mastering Percentage Calculations for Everyday Life & Business
A Percentage represents a fraction of 100, symbolized by '%'. Whether you are calculating shopping discounts during a festival sale, determining profit margins for a business, checking school exam grades, or calculating tax tips, percentage arithmetic is a fundamental mathematical tool used every day.
Essential Percentage Formulas
- What is X% of Y? → Result = (X / 100) × Y
- X is what % of Y? → Result = (X / Y) × 100
- Percentage Increase: → [ (New - Old) / Old ] × 100
- Percentage Decrease: → [ (Old - New) / Old ] × 100
Real-World Practical Uses
- Retail Discounts: Instantly check how much you save on a 30% off tag.
- Financial Margins: Calculate gross profit and net profit percentage ratios.
- Academic Grading: Convert raw exam scores and GPA into aggregate percentage.
Frequently Asked Questions (FAQs)
What is the difference between Percentage and Percentage Point?
A Percentage refers to a proportional rate of change relative to an initial value, whereas a Percentage Point refers to the simple numerical difference between two percentages. For example, if a bank interest rate increases from 8% to 10%, it has increased by 2 percentage points, but proportionally it is a 25% percentage increase (since 2 is 25% of 8).
How do I calculate a reverse percentage to find the original price before discount?
To find the original price before a percentage discount was applied, divide the final sale price by (1 - Discount%/100). For example, if you paid ₹800 for a shirt after a 20% discount, calculate: ₹800 / (1 - 0.20) = ₹800 / 0.80 = ₹1,000 original price.
Why is a 50% increase followed by a 50% decrease not equal to the starting number?
Percentages always apply to the current base value. If you start with ₹100 and increase it by 50%, you get ₹150. If you then decrease ₹150 by 50%, you subtract half of 150 (₹75), leaving you with ₹75 instead of your starting ₹100. Because the second calculation uses a larger base number, a equal percentage decrease has a greater absolute impact.
What is X% of Y?
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X is what % of Y?
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Percentage Increase / Decrease
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Frequently Asked Questions
How do I calculate percentage?
To find the percentage of a number, multiply the number by the percentage fraction. For example, 20% of 50 is (20/100) * 50 = 10.
How is percentage increase calculated?
To calculate percentage increase: subtract the old value from the new value, divide the result by the old value, and multiply by 100.