Discount Calculator

Enter the original price and the discount percentage to see the savings and the final sale price.

What Is a Discount?

A discount is a reduction in price stated as a percentage of the original price. It is the retail-facing form of percentage decrease. Every "20% off" sign on a store window is the same calculation as the percentage decrease formula applied to a price tag instead of a generic number.

Stores use discounts for a handful of concrete reasons: to clear seasonal inventory before new stock arrives, to reward loyal customers, to move slow sellers, and to compete on price during a sale event. Whatever the reason, the underlying arithmetic never changes. A discount rate is applied to an original price to produce a smaller sale price, and the difference between the two is the amount saved. Understanding that one relationship lets a shopper check any advertised deal in seconds, without trusting the sign in the window to have done the math correctly.

How to Calculate a Discount

Calculating a discount takes three short steps. Each one is simple on its own, and together they turn a percentage on a sign into an actual dollar figure you can compare against other offers.

Step 1: Convert the Discount Percent to a Decimal

Divide the advertised percentage by 100. A 30% discount becomes 0.30. This decimal is the rate you will multiply against the price in the next step, so getting this conversion right matters more than any other part of the calculation.

Step 2: Multiply by the Original Price

Multiply the decimal rate by the original price to find the dollar amount of the discount. On a $150 jacket at a 30% discount, that is 150 × 0.30 = $45. That $45 is how much the shopper saves, not the final price they pay.

Step 3: Subtract to Find the Sale Price

Subtract the discount amount from the original price. Continuing the example, 150 − 45 = $105. That is the price at the register before tax. As a shortcut, the same answer comes from multiplying the original price once by (1 − 0.30) = 0.70, since 150 × 0.70 = $105 in a single step.

Common Mistakes

The most common mistake with discounts is stacking two or more of them by adding the percentages together. Two 20% discounts do not combine into 40% off. Each discount applies to whatever price remains after the previous one, so the correct calculation multiplies the two multipliers: 1 − 0.80 × 0.80 = 1 − 0.64 = 0.36, a 36% total reduction, not 40%. The gap grows with every additional discount stacked on top, so a shopper comparing "40% off" language against a real receipt should always work through the multipliers rather than trust the sum. A second common error is applying the discount to a price that already includes tax, which overstates the savings; the discount should always be calculated on the pre-tax price unless a store's policy states otherwise.

Discount Formula

Sale Price = Original × (1 − Discount% / 100). Savings = Original − Sale Price. The first formula gets you straight to the register price in one multiplication. The second formula is useful whenever the number you actually care about is how much you kept in your pocket rather than what you paid.

Discount vs Percentage Decrease

The two are the same calculation in different wrapping. "Discount" speaks to a shopper standing in front of a price tag; "percentage decrease" speaks to an analyst comparing two numbers in a spreadsheet. Both produce the same multiplier and the same final value, and both start from an original value and end at a smaller one. The only real difference is vocabulary: a store calls the original value the "regular price" and the new value the "sale price," while a general percentage decrease calculation just calls them "original" and "new." Anyone comfortable with one version already understands the other.

Real-World Discount Examples

1. Clothing sale, $80 shirt at 25% off: Convert 25% to 0.25, multiply by $80 to get a $20 discount, then subtract: 80 − 20 = $60 sale price. The shortcut confirms it: 80 × 0.75 = $60.

2. Electronics Black Friday deal, $1,200 laptop at 30% off: 1,200 × 0.30 = $360 saved. 1,200 − 360 = $840 final price. A shopper comparing this against a competitor's "$850, no discount" listing can see the 30%-off laptop is the better deal by $10 even before considering any extra coupon.

3. Restaurant coupon, $45 dinner check at 15% off: 45 × 0.15 = $6.75 saved, bringing the check to 45 − 6.75 = $38.25 before tip and tax. Restaurant coupons commonly apply only to the food total, not to drinks or gratuity, so the discount amount should be worked out on the eligible portion of the bill only.

4. Membership or loyalty discount, $65 order at 10% off for members: 65 × 0.10 = $6.50 saved, for a member price of 65 − 6.50 = $58.50. Loyalty discounts are usually smaller per-purchase than a seasonal sale, but they apply every time a member shops, so the savings compound across a year of repeat purchases in a way a single clearance discount cannot.

5. Bulk-order trade discount, $2,500 wholesale order at 12% off for ordering over 100 units: 2,500 × 0.12 = $300 saved, for a net order total of 2,500 − 300 = $2,200. Trade and volume discounts like this one are common in business-to-business sales, where the percentage is set by contract rather than posted on a sign, but the arithmetic underneath is identical to a retail sale.

Seasonal Inventory Reduction and Retail Markdown Planning

Retailers schedule markdowns to move inventory before a new season starts, and they plan the schedule around multiplication, not addition. A typical sequence might run 20% off in week one, 40% off in week three, 60% off in week five, and clearance pricing at 75% off in week seven, with each new markdown calculated against the original list price rather than the already-reduced price.

Clearance events work differently, and this is where stacked-discount confusion shows up most often on a receipt. Consider an item marked down 20% during the regular sale, then a further 15% off the already-reduced price once it reaches the clearance rack. A $100 item first drops to 100 × 0.80 = $80. The clearance discount then applies to that $80, not to the original $100: 80 × 0.85 = $68. The total reduction from the original price is 1 − 0.80 × 0.85 = 1 − 0.68 = 32%, not the 35% a shopper would get by simply adding 20% and 15% together. Retail planners rely on the multiplicative version because it composes cleanly across any number of markdown steps, and it is the only version that matches what actually rings up at the register.

The same logic scales up to a full season. Stacking three markdowns of 20%, 25%, and 30% in sequence gives 0.80 × 0.75 × 0.70 = 0.42, a 58% total reduction from the original list price, even though the three individual rates only add up to 75%. Inventory planners build clearance calendars around these compounding multipliers so that a season's final markdown lands at a predictable price point rather than an accidental one.

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