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Percentage Calculator
Quickly solve common percentage problems: finding percentages, percentage increases/decreases, and fraction equivalents.
What is X% of Y?
%
Formula & Explanation
Formula: (15 / 100) * 200 = 30
Divide the percentage by 100, then multiply by the total value.
Result Value
30
X is what percent of Y?
Formula & Explanation
Formula: (25 / 125) * 100 = 20%
Divide the part (X) by the whole (Y), then multiply by 100 to get the percentage.
Result Percentage
20%
Percentage Increase/Decrease
Formula & Explanation
Formula: ((100 - 80) / 80) * 100 = 25%
Subtract the initial value from the final value, divide by the absolute initial value, then multiply by 100.
Percentage Change
25% increase
▲+25%
Percentage Difference
Formula & Explanation
Formula: (|80 - 100| / ((80 + 100) / 2)) * 100 = 22.22%
Divide the absolute difference between the two values by their average, then multiply by 100. Used when comparing two values where neither is a baseline.
Percentage Difference
22.22%
Increase X by Y%
%
Formula & Explanation
Formula: 120 * (1 + 10 / 100) = 132
Multiply the base value by (1 + percentage/100).
Increased Value
132
Decrease X by Y%
%
Formula & Explanation
Formula: 120 * (1 - 10 / 100) = 108
Multiply the base value by (1 - percentage/100).
Decreased Value
108
Percentage to Fraction
%
Formula & Explanation
Formula: 37.5% = 37.5 / 100 = 3/8
Put the percentage over a denominator of 100 and simplify to the lowest common fraction. Divide by 100 to find the decimal.
Fraction & Decimal
3/8 (0.375)
Fraction to Percentage
Formula & Explanation
Formula: (3 / 8) * 100 = 37.5%
Divide the numerator by the denominator, then multiply by 100 to get the percentage value.
Percentage Result
37.5%
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Frequently Asked Questions
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What kinds of percentage calculations can this tool perform?
It can calculate basic percentages, percentage increases or decreases (percentage change), find what percentage one number is of another, and convert fractions to percentages.
Does the calculator update values in real-time?
Yes, as you type numbers into any field, the calculator instantly computes and displays the correct result without needing to submit a form.
Are my calculations private and secure?
Yes. All math equations and inputs are calculated locally using client-side JavaScript. No data is stored or sent over the internet.