X is what percentage of Y?
Find what percentage one number is of another — e.g. 50 of 200.
Formula & step-by-step solution
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Percent Calculator
Find what percentage one number is of another — e.g. 50 of 200.
Open calculatorProfit & Loss Calculator
Profit, loss, %, selling price, cost price, margin and markup in one place.
Open calculatorSales Tax / GST Calculator
Add tax to a price, or remove tax from a tax-inclusive total.
Open calculatorAge Calculator
Exact age in years, months and days, age difference, birthday countdown and date difference.
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Trigonometry, logarithms, powers, roots, factorials, memory and history.
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Convert INR, USD, EUR, GBP, AED and 160+ currencies with daily updated rates.
Open calculatorWhy Use Our Percentage Calculator?
Built to be the quickest way to get a correct answer — and understand it.
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Floating-point errors are cleaned up and edge cases are handled.
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Six tools in one place
Percent, GST, profit & loss, age, scientific and currency.
Frequently Asked Questions
Quick answers about percentage calculations.
How do I calculate a percentage?
Divide the part by the total and multiply by 100. For example, 30 out of 120 is 30 ÷ 120 × 100 = 25%. You can use our Percent Calculator to do it instantly.
How do I find a percentage of a number?
Convert the percentage to a decimal by dividing by 100, then multiply. 20% of 500 = 0.20 × 500 = 100.
What is the formula for percentage increase?
Percentage increase = (New value − Original value) ÷ Original value × 100. From 100 to 150 the increase is 50%.
What is the difference between percentage change and percentage difference?
Percentage change compares a new value to an old (reference) value. Percentage difference compares two values with no direction, using their average as the reference.
How do I reverse a percentage to find the original value?
Divide the final value by (1 + percentage ÷ 100) for an increase, or by (1 − percentage ÷ 100) for a decrease. 120 after a 20% increase was originally 120 ÷ 1.2 = 100.
Is a 50% increase followed by a 50% decrease the same value?
No. 100 increased by 50% is 150, and 150 decreased by 50% is 75. Each percentage is applied to a different base value.
What is the difference between percent and percentage points?
Percentage points measure the simple difference between two percentages. A rate rising from 4% to 6% is a 2 percentage-point rise, but a 50% increase.
Can I use negative numbers and decimals?
Yes. All calculators accept decimals, and negative numbers wherever they make mathematical sense. Values that would cause division by zero show a clear error message instead.
Is Calculatorza free to use?
Yes. Every calculator is completely free, needs no registration, and runs directly in your browser.
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