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% Percentage Calculator

Every percentage problem you'll ever need, in one tool. All calculations update live as you type — pure JavaScript, no rounding tricks.

What is X% of Y?

Find a percentage of a value. e.g. 15% of 200 = 30.

% of —

X is what % of Y?

Find what percentage one number is of another.

is what % of —

X is Y% of what?

Reverse percentage: find the original number.

is % of what? —

Percent change (X → Y)

Increase or decrease as a percentage. Negative = decrease.

From to —

Increase by %

Add a percentage to a number.

+ % —

Decrease by %

Subtract a percentage from a number.

− % —

Tip calculator

Bill amount + tip percent = total & tip portion.

Bill + % —

Markup vs. Margin

Cost & selling price → margin %, markup %, profit.

Cost Sell —