How do I calculate a discount?

Multiply the original price by the discount percentage, then divide by 100 to get the discount amount. Subtract that from the original price for the sale price. For example, 25% off a $80 item: $80 × 25 / 100 = $20 discount, so the sale price is $60.

How do stacked discounts work?

Stacked (double) discounts are applied sequentially, not added together. A 20% off plus an extra 10% off is NOT 30% off. First apply 20% to the original: $100 becomes $80. Then apply 10% to $80: you get $72. The total discount is actually 28%, not 30%.

Is the discount applied before or after tax?

Discounts are applied to the pre-tax price. Sales tax is then calculated on the discounted price. So if a $100 item is 20% off with 8% tax: the discounted price is $80, tax is $6.40, and the total is $86.40.

How do I calculate the original price from a sale price?

Divide the sale price by (1 - discount%/100). For example, if something costs $60 after a 25% discount: $60 / (1 - 0.25) = $60 / 0.75 = $80 original price. This is useful when a store shows only the sale price without the original.

Is it better to get a percentage discount or a fixed dollar amount off?

It depends on the price. On a $50 item, 20% off ($10) is better than $8 off but worse than $12 off. On expensive items, percentage discounts tend to save more. Always calculate the actual dollar savings to compare, this calculator makes that easy.

Discount Calculator

Calculate the sale price after a percentage discount. See exactly how much you save, handle double discounts, and add sales tax to get the final price.

By InstaCalcs Team·Calculation reviewed·Report an issue

Original Price

Discount Percentage

Sales Tax Rate (optional)

Double Discount (Stacked)

Second Discount Percentage (optional)

Apply a second discount to the already-discounted price for stacked promotions.

Price Breakdown

Original Price$100.00

1st Discount (20.0%)-$20.00

After 1st Discount$80.00

Summary

Final Price (after discount)

$80.00

You Save

$20.00(20.0% off)

How to use

Enter the original price and discount percentage to see the sale price and your savings. Optionally add a sales tax rate to calculate the final out-of-pocket cost. For stacked promotions (like "20% off + extra 10% for members"), enter the second discount to see the true combined savings.

Formula

Sale Price = Original Price × (1 - Discount% / 100)

For double discounts, apply each discount sequentially: first calculate the price after the first discount, then apply the second discount to that reduced price. The total effective discount is always less than the sum of the two individual discounts.

When this calculator helps

Sales, promotions, and coupon codes are everywhere, but it can be surprisingly hard to calculate the true final price, especially with stacked discounts, member coupons, and sales tax. This calculator is perfect for shoppers comparing deals during Black Friday or seasonal sales, retailers setting promotional pricing, and anyone who wants to know exactly what they will pay before reaching the checkout. It eliminates the mental math and reveals whether a "double discount" deal is actually as good as it sounds, helping you make smarter purchasing decisions.

Examples

Example 1: Black Friday Electronics Deal

A $799 laptop is 30% off for Black Friday. The discount is $239.70, bringing the price to $559.30. With 7% sales tax, the final price is $598.45. You save $200.55 off the full retail price plus tax, a meaningful saving that justifies waiting for the sale.

Example 2: Stacked Clothing Store Coupons

A $120 jacket is 40% off, and you have an additional 15% member coupon. First discount: $120 × 0.60 = $72. Second discount: $72 × 0.85 = $61.20. The combined effective discount is 49%, not 55%, you save $58.80 instead of the $66 you might expect.

Example 3: Grocery Bulk Buy Comparison

A store offers "Buy 2, Get 1 Free" on $6.99 items. This is effectively a 33.3% discount when buying three. The total is $13.98 instead of $20.97, saving $6.99. Compare this to a competing store's flat 25% off ($5.24 each, $15.73 for three) to see which deal is better.

Things to watch

•Stacked discounts are multiplicative, not additive, 20% + 10% off equals 28% total, not 30%. Always calculate the actual savings.
•Watch out for inflated "original" prices, some retailers raise prices before a sale to make the discount appear larger than it really is.
•A good deal on something you do not need is not actually a saving. Focus on items you planned to buy rather than impulse purchases just because they are discounted.
•Compare the per-unit price when evaluating bulk discounts, sometimes the "deal" size is actually more expensive per ounce or per item.
•Remember that sales tax varies by state (0-10.25%) and can change your final out-of-pocket cost, especially on big-ticket items.

Sources and methodology

Last reviewed: Checked during calculator QA. We review formulas, default assumptions, and examples against public references when a formal source applies.

Method: This calculator uses the formula explained on this page. We also check example results by hand to catch obvious mistakes.

Found something off? Send a correction with the page URL, inputs, result, and expected result.

Common questions

How do I calculate a discount?: Multiply the original price by the discount percentage, then divide by 100 to get the discount amount. Subtract that from the original price for the sale price. For example, 25% off a $80 item: $80 × 25 / 100 = $20 discount, so the sale price is $60.
How do stacked discounts work?: Stacked (double) discounts are applied sequentially, not added together. A 20% off plus an extra 10% off is NOT 30% off. First apply 20% to the original: $100 becomes $80. Then apply 10% to $80: you get $72. The total discount is actually 28%, not 30%.
Is the discount applied before or after tax?: Discounts are applied to the pre-tax price. Sales tax is then calculated on the discounted price. So if a $100 item is 20% off with 8% tax: the discounted price is $80, tax is $6.40, and the total is $86.40.
How do I calculate the original price from a sale price?: Divide the sale price by (1 - discount%/100). For example, if something costs $60 after a 25% discount: $60 / (1 - 0.25) = $60 / 0.75 = $80 original price. This is useful when a store shows only the sale price without the original.
Is it better to get a percentage discount or a fixed dollar amount off?: It depends on the price. On a $50 item, 20% off ($10) is better than $8 off but worse than $12 off. On expensive items, percentage discounts tend to save more. Always calculate the actual dollar savings to compare, this calculator makes that easy.