Calculators and Converters

How to Calculate Percentage: Marks and Discounts

By MayreDukaan Editorial TeamPublished 15 Nov 20264 min read

Illustration: a pie chart with one slice lifted out, a green calculator, a receipt and a percent sign made of coins

Use a percentage calculator for exam marks, discounts and price changes in Pakistan. Learn the formulas with clear examples in rupees.

A percentage calculator answers three different questions: what a percentage of an amount is, what percentage one number is of another, and how much a value has increased or decreased. Choose the right question first. For exam marks, divide obtained marks by total marks and multiply by 100; for a discount, multiply the original price by the discount percentage and divide by 100.

The MayreDukaan percentage calculator has separate sections for these calculations. Here is how to use them for Pakistani school results, shopping and everyday price comparisons without mixing up the base number.

What percentage means

Percent means per hundred. A result of 75% means 75 out of every 100 equal parts. To use a percentage in multiplication, divide it by 100: 15% becomes 0.15, while 2.5% becomes 0.025. The same method works with marks, rupees or quantities, as long as the numbers refer to comparable things.

Question	Formula	Example
What is X% of Y?	X ÷ 100 × Y	15% of Rs 2,500 = Rs 375
X is what percent of Y?	X ÷ Y × 100	45 out of 60 = 75%
Percentage change	(New − old) ÷ old × 100	Rs 800 to Rs 1,000 = 25% increase

The change formula shown here is for a positive original value. If the original value is zero, percentage change is undefined. The tool displays a dash rather than a finite answer when the required denominator is zero.

Calculate exam marks as a percentage

Suppose a student obtains 875 marks out of 1,100. The calculation is 875 ÷ 1,100 × 100 = 79.545454…%. Rounded to two decimal places, that is 79.55%.

Open the percentage calculator.
Find “X is what percent of Y?”
Enter 875 in Value and 1100 in Total.
Read the percentage and round only as required by the receiving form.

For several subjects, add the obtained marks and the maximum marks separately before dividing. Imagine scores of 80 out of 100 and 45 out of 50. The combined result is 125 ÷ 150 × 100 = 83.33%, rounded. Simply averaging 80% and 90% would give 85%, which incorrectly gives both subjects equal weight despite their different maximum marks.

This calculator does not convert percentages to CGPA or determine an admissions aggregate. If a Pakistani institution asks for either, use its published conversion or weighting rules rather than assuming one universal relationship. Keep your raw marks available so the calculation can be checked.

Find discounts and final prices in rupees

For a shirt priced at Rs 2,500 with 15% off, calculate 2,500 × 15 ÷ 100 = Rs 375. That is the saving, not the amount to pay. Subtract it from the original price: Rs 2,500 − Rs 375 = Rs 2,125.

Use the discount calculator if you want the final price and saving together, especially when a second discount follows the first. For example, 20% off Rs 2,500 leaves Rs 2,000. A further 10% off that balance saves Rs 200, leaving Rs 1,800. The overall reduction is Rs 700, or 28%, not 30%.

Treat these as price-only examples. Check delivery and any separately stated charges before deciding whether a purchase fits your budget. The percentage calculation cannot tell you which charges a particular seller includes.

Measure an increase or decrease

A price rising from Rs 800 to Rs 1,000 has increased by Rs 200. Divide that change by the original Rs 800: 200 ÷ 800 × 100 = 25%. Enter 800 under From and 1000 under To in the calculator’s change section.

Going back from Rs 1,000 to Rs 800 is a 20% decrease, because the original value is now Rs 1,000. Equal rupee changes need not produce equal percentage changes. Always identify the starting point before calculating.

Percentage points are different again. Moving from 60% to 75% is an increase of 15 percentage points. Relative to the starting 60%, it is a 25% increase. State which comparison you mean when discussing marks or rates.

Common mistakes to avoid

Dividing maximum marks by obtained marks instead of the other way around.
Reporting the discount amount as the final sale price.
Adding successive discounts without checking the new base.
Rounding every intermediate calculation instead of the final result.
Confusing markup on cost with margin on selling price.

For the last distinction, use the profit margin calculator. Buying for Rs 800 and selling for Rs 1,000 produces Rs 200 profit: a 25% markup on cost but a 20% margin on selling price.

Choose the calculation before entering numbers

Write the question in words, identify the whole or original amount, then enter the two values in the matching section. Calculations update in the browser as you type. Start with the percentage calculator, and keep both your inputs and rounded answer when you need a result for a form or price record.

Frequently asked questions

How do I calculate my marks percentage?

Divide obtained marks by total possible marks and multiply by 100. For 875 out of 1,100, the result is about 79.55%.

Is a 20% discount followed by 10% off equal to 30%?

No. The second discount applies to the reduced price, making the combined reduction 28%.

Can I calculate percentage change from zero?

No. The formula requires division by the original value, so a zero starting value has no defined percentage change.

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Sources

Facts last checked against these sources on 15 Nov 2026, 07:43 Pakistan time.

Images: Illustration created for MayreDukaan (not a photo)