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Percentage Calculator

Calculate discounts, markups, percentage shifts and ratios instantly.

How to Use This Tool

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1. Select Calculation Type

Choose your calculation mode (X% of Y, percentage change, or discount/markup).

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2. Input Numbers

Type the known values into the respective fields.

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3. View Instant Results

Get your calculated result instantly alongside detailed step-by-step math breakdowns.

Frequently Asked Questions about Percentage Calculations

How do I calculate a discount percentage on a purchase?

To apply a 20% discount on $150, multiply 150 by 0.20 ($30 discount amount, final price $120).

How do I calculate percentage growth between two numbers?

Subtract the old value from the new value, divide by the old value, and multiply by 100.

Does the percentage calculator work offline?

Yes! All calculations run client-side in your browser JavaScript engine without needing active server requests.

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