Enter any two values to solve three common percentage problems: find what % of a number is, calculate what percentage one number is of another, or determine what number a percentage represents. You also get a percentage change calculator to find increase or decrease between two values. Results appear across all four calculators as you type.
What is X% of Y?
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X is what % of Y?
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X is Y% of what?
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Percentage Change
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Change Direction
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A percentage is a way of expressing a number as a fraction of 100. The word comes from the Latin 'per centum', meaning 'by the hundred'. It is denoted by the '%' symbol. For example, 45% means 45 out of every 100.
Divide the part by the whole, then multiply by 100. For example, if 30 out of 150 students passed, the percentage is (30 ÷ 150) × 100 = 20%. This is the most common percentage calculation.
Multiply the number by the percentage and divide by 100. For example, 25% of 200 is (25 × 200) ÷ 100 = 50. Alternatively, convert the percentage to a decimal (25% = 0.25) and multiply: 0.25 × 200 = 50.
Subtract the original value from the new value, divide by the original value, then multiply by 100. The formula is: ((New − Original) ÷ Original) × 100. A positive result means an increase; a negative result means a decrease.
If the new value is greater than the original, the result is a percentage increase. If the new value is less than the original, the result is a percentage decrease. The same formula applies to both — the sign of the result tells you the direction.
Divide the known part by the percentage and multiply by 100. For example, if 50 is 20% of a number, the original is (50 ÷ 20) × 100 = 250. This is the 'reverse percentage' calculation.
Percentages appear everywhere — discounts in shops, interest rates on loans, tax rates, exam scores, and statistical data. They provide a standardised way to compare proportions regardless of the scale of the underlying values.
Yes. A percentage greater than 100% simply means the part exceeds the whole in a comparison context, or that a value has more than doubled in a percentage change scenario. For example, if sales grew from 50 to 120, that is a 140% increase.