Basic formula
Percentage formula
Percentage = (Part ÷ Whole) × 100
For 50 out of 200: (50 ÷ 200) × 100 = 25%.
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Percentage calculations, made clear.
Calculate percentages, marks, increases, discounts, CGPA conversions, profit and loss instantly — with one fast, mobile-friendly tool.
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Choose a calculation
Your result
100
20% of 500
Percentage
20%
Base value
500
Result
100
The basics
How to calculate percentage
A percentage expresses a number as parts per hundred. Divide the value you are measuring by the total or reference value, then multiply by 100.
The right formula depends on the question: percentage of a value, percentage change, percentage difference and discount calculations use different reference values.
Marks
Percentage of marks
(Marks obtained ÷ Total marks) × 100
420 out of 500 is 84%. The total marks must be greater than zero.
Change
Increase or decrease
((New − Old) ÷ |Old|) × 100
The sign tells you the direction. Percentage change from zero is undefined.
Education
CGPA to percentage
The calculator uses CGPA × conversion multiplier, with 9.5 as the default multiplier because it is a commonly used estimate in India.
There is no single universal CGPA conversion formula. Universities, boards and institutions may use different multipliers or methods, so verify the official formula before using a result on an application or official document.
Quick reference
Common percentage examples
20% of 500 = 100
50 is 25% of 200
500 → 600 = 20% increase
₹2,000 at 10% off = ₹1,800
Questions, answered
Percentage calculator FAQs
How do I calculate a percentage?
To calculate a percentage, divide the part by the whole and multiply by 100. For example, 50 ÷ 200 × 100 = 25%.
How do I calculate percentage of marks?
Divide marks obtained by total marks and multiply by 100. For example, 420 out of 500 is 420 ÷ 500 × 100 = 84%.
How do I calculate percentage increase or decrease?
Subtract the old value from the new value, divide by the absolute old value, and multiply by 100. A positive result is an increase and a negative result is a decrease. An old value of zero has no defined percentage change.
How is CGPA converted to percentage?
A common estimate is CGPA × 9.5, but conversion formulas vary by university, board and course. Check your institution's official formula before using the result for admissions, applications or official records.
What is percentage difference?
Percentage difference compares two values without treating either as the original baseline: absolute difference ÷ average of the two values × 100. When both values are zero, the calculation is undefined.
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