Percentage Calculator – %, Increase and Share

Three questions account for almost every percentage calculation in daily life: What is 20% of 500? 45 is what percent of 90? Did sales rise or fall from 120 to 150? This tool answers all three instantly — useful for exam scores, discounts, tips and growth rates.

The formula

% = part ÷ whole × 100

FAQ

How do I calculate percentage increase?

Subtract the old value from the new, divide by the old value, multiply by 100. From 120 to 150: (30 ÷ 120) × 100 = +25%.

Is a 10% rise then 10% fall break-even?

No — you end 1% lower, because the fall applies to the larger base. Percentage changes are always relative to their starting value.

How do I reverse a percentage?

To undo a 20% discount from ₹480, divide by 1.20 (not multiply): the original was ₹400.

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