Percentage Calculator - Calculate Percentages, Changes & Discounts
Use our free percentage calculator to calculate percentages, percentage changes, increases, and decreases. Our percentage calculator helps you find percentage of a number, percentage change, percentage increase, percentage decrease, discounts, markups, and profit margins. Perfect for discount calculator calculations, markup calculator planning, and percentage change calculator analysis.
Calculate percentages for discounts, sales, tax calculations, tip calculations, and financial analysis. Get instant results with step-by-step explanations and formulas.
What is X% of Y?
Example: What is 20% of 150?
Frequently Asked Questions About Percentages
How do I calculate a percentage of a number?
To calculate a percentage of a number, multiply the number by the percentage divided by 100. For example, to find 20% of 150: 150 × (20/100) = 150 × 0.20 = 30. Our percentage calculator does this automatically - just enter the percentage and the number, and get instant results with step-by-step explanations.
What's the difference between percentage increase and percentage change?
Percentage increase shows how much a value has grown (always positive), while percentage change can be positive (increase) or negative (decrease). Both use the formula: ((New Value - Old Value) / Old Value) × 100. For example, if a price goes from $100 to $120, that's a 20% increase. If it goes from $100 to $80, that's a -20% change (20% decrease). Our calculator handles both calculations automatically.
How do I calculate discounts and sale prices?
To calculate a discount, multiply the original price by the discount percentage divided by 100, then subtract from the original. For example, 15% off $200: Discount = $200 × 0.15 = $30, Sale Price = $200 - $30 = $170. Alternatively, multiply by (1 - discount percentage): $200 × 0.85 = $170. Our percentage calculator includes a "Percentage Off" mode that calculates discounts and final prices instantly.
What's the difference between markup and profit margin?
Markup is calculated on the cost price: ((Selling Price - Cost) / Cost) × 100. Profit margin is calculated on the selling price: ((Selling Price - Cost) / Selling Price) × 100. For example, if you buy for $50 and sell for $75: Markup = 50%, Margin = 33.3%. Markup shows how much you add to cost, while margin shows what percentage of the selling price is profit. Our calculator includes both markup and margin calculations.
How do I reverse calculate a percentage?
To find the original number when you know a value and what percentage it represents, divide the value by the percentage (as a decimal). For example, if 25 is 20% of a number: Original = 25 ÷ 0.20 = 125. Our percentage calculator includes a "Reverse Percentage" mode that finds the original number when you know a value and its percentage.
Can I use this calculator for tax and tip calculations?
Yes! Our percentage calculator is perfect for calculating tax (e.g., 10% GST on $100 = $10), tips (e.g., 15% tip on $50 = $7.50), and other percentage-based fees. Simply use the "Percentage of a Number" mode: enter the tax/tip percentage and the amount, and get instant results. This is especially useful for Australian GST calculations (10%) and service industry tip calculations.