Discount Percentage Calculator
Find out exactly what percentage discount you received based on the original and sale prices.
Enter your values and click Calculate
Retailers often advertise sale prices without showing the discount percentage, making it difficult to compare deals or verify whether a markdown is meaningful. This calculator works backwards from the original price and the final sale price to reveal the exact percentage you saved. It handles everyday shopping comparisons, car price negotiations, supplier bulk-buy discounts, and real estate price reductions. If the sale price exceeds the original — as happens with ticket scalping or price gouging — the calculator returns a negative discount, correctly indicating a markup rather than a saving. The result includes both the percentage and the raw dollar amount saved so you have the full picture at a glance.
How It Works
The formula is: Discount % = ((Original Price − Sale Price) ÷ Original Price) × 100. First, the amount saved is found by subtracting the sale price from the original price. That saving is then expressed as a fraction of the original price by dividing, and finally multiplied by 100 to convert to a percentage. For example, a $120 jacket reduced to $90: savings = $120 − $90 = $30; discount = ($30 ÷ $120) × 100 = 25%. When the sale price is higher than the original, the savings figure becomes negative, and the resulting negative percentage correctly signals a premium or markup. The original price must be greater than zero, since dividing by zero is undefined.