Percentage Calculator

Frequently asked questions

How do I calculate X% of a number?

To calculate X% of a number, multiply the number by X and divide by 100. For example, 25% of 200 = (200 × 25) ÷ 100 = 50. Use our 'What is X% of Y' calculator mode for instant results. This is useful for calculating discounts, commissions, or any portion of a value.

What's the difference between percentage change and percentage difference?

Percentage change measures the relative change from an original value to a new value: ((New - Old) ÷ Old) × 100. It's directional and shows increase or decrease. Percentage difference compares two values relative to their average: (|V1 - V2| ÷ Average) × 100. It's non-directional and used when neither value is the 'original.' Use percentage change for growth rates, price changes, or performance over time. Use percentage difference for comparing two independent values.

How do I calculate a percentage increase or decrease?

Calculate the change amount (New Value - Original Value), divide by the original value, then multiply by 100: ((New - Old) ÷ Old) × 100. A positive result is an increase, negative is a decrease. For example, from 100 to 150: ((150 - 100) ÷ 100) × 100 = 50% increase. Use our 'Percentage Change' calculator mode for automatic calculation of increases and decreases.

What's the difference between markup and margin?

Markup is calculated on cost: (Selling Price - Cost) ÷ Cost × 100. Margin is calculated on selling price: (Selling Price - Cost) ÷ Selling Price × 100. For example, if cost is $50 and selling price is $100: Markup = ($100 - $50) ÷ $50 = 100%, but Margin = ($100 - $50) ÷ $100 = 50%. Retailers often use markup for pricing decisions, while margin is preferred for profitability analysis. A 100% markup equals 50% margin.

How do I calculate the original price before a discount?

If you know the discounted price and the discount percentage, use the formula: Original Price = Discounted Price ÷ (1 - Discount%/100). For example, if an item costs $80 after a 20% discount: $80 ÷ (1 - 0.20) = $80 ÷ 0.80 = $100. Use our 'X is Y% of what?' calculator mode by entering the discounted price and the remaining percentage (100% - discount%).

How do I add or subtract a percentage from a number?

To add X%: New Value = Original × (1 + X/100). To subtract X%: New Value = Original × (1 - X/100). For example, to add 20% to 100: 100 × 1.20 = 120. To subtract 20% from 100: 100 × 0.80 = 80. Use our 'Add/Subtract Percentage' calculator mode for instant results. This is useful for price increases, tax calculations, or applying discounts.

What is a percentage point difference?

Percentage points measure the arithmetic difference between two percentages. If a rate goes from 25% to 45%, that's a 20 percentage point increase, not a 20% increase. The actual percentage increase would be ((45-25)÷25)×100 = 80% increase. Percentage points are absolute differences, while percentage changes are relative. This distinction is important in finance, economics, and statistics when discussing interest rates, tax rates, or survey results.

How do I calculate VAT or sales tax?

To add VAT to a price: Price with VAT = Price × (1 + VAT%/100). For example, $100 + 20% VAT = $100 × 1.20 = $120. To extract VAT from an inclusive price: VAT amount = Price ÷ (1 + VAT%/100), then subtract from total. For example, if $120 includes 20% VAT: Price without VAT = $120 ÷ 1.20 = $100, VAT = $20. Use our VAT/Tax calculator mode for both inclusive and exclusive calculations.