Percentage Calculator

Five common percentage questions, answered as you type.

What is % of

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is what % of

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Change from to

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Increase by %

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Decrease by %

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Formulas

X% of Y = Y × X ÷ 100
X is what % of Y = X ÷ Y × 100
Percent change = (new − old) ÷ old × 100
Increase by P% = value × (1 + P ÷ 100)
Decrease by P% = value × (1 − P ÷ 100)

Examples

A 20% discount on 80 is 16, so the sale price is 64. If a price goes from 50 to 65, that is a 30% increase. Note that a 50% decrease followed by a 50% increase does not return you to the start: 100 → 50 → 75.

FAQ

How do I calculate a discount?

Use “Decrease by” with the original price and the discount percentage.

How do I add tax or a tip?

Use “Increase by” with the price and the tax or tip rate.