Finance

Discount Calculator

Work out the sale price, stack up to three discounts plus a coupon, and add sales tax, or work backward from a sale price to the original price.

Your price

Final price

—

You saved

—

Effective discount

—

Price breakdown

You pay —You save —

Price before tax: —· Sales tax: —· Total: —

Show the math

Sale price = original × (1 − d1) × (1 − d2) × (1 − d3) − coupon

Estimate only — actual checkout totals may differ slightly due to rounding or retailer-specific rules on how stacked discounts and tax are applied.

How to calculate a discount

Sale Price = Original Price × (1 − Discount% ÷ 100). For a $100 item at 20% off, that's $100 × 0.80 = $80, a savings of $20. The calculator does that instantly, and extends the same math to stacked discounts, a dollars-off coupon, and sales tax. For a quick check, 10% of any price is that price with the decimal point moved one place left, so 30% off a $60 item is 3 × $6 = $18 off.

Finding the original price before a discount

Run the formula in reverse: Original Price = Sale Price ÷ (1 − Discount% ÷ 100). If an item is $80 after a 20% discount, the original price was $80 ÷ 0.80 = $100. This is handy for double-checking whether an advertised "20% off" sticker actually matches the price difference shown at checkout. Switch "Find the" to "Original price" above and enter the sale price. The calculator reverses any stacked discounts and coupon too: it adds the coupon back, then divides by (1 − d1) × (1 − d2) × (1 − d3). A common slip is to add 20% back onto $80, which gives $96, not $100, because the 20% was taken from the larger original price.

Stacking multiple discounts

Stacked discounts multiply rather than add — each one applies to the price left over after the previous discount, not to the original price. A 20% discount followed by a 10% discount isn't 30% off; it's 1 − (0.80 × 0.90) = 28% off. Enter a second or third discount (for example, a sale price plus an extra 10% at the register) and the calculator stacks them in order and reports the true combined "effective discount" rate. The order of percentage discounts doesn't change the result, since multiplication works in any order.

Discount + sales tax together

Apply the discount first, then calculate tax on what's left — tax is charged on the price you actually pay, not the original sticker price. For a $100 item at 20% off with 8% sales tax: the discounted price is $80, tax adds $80 × 0.08 = $6.40, for a final total of $86.40. This calculator applies tax in that same order automatically. For the tax step on its own, or to back tax out of a receipt total, use the sales tax calculator.

Percent-off quick table

Sale prices before tax for common discounts. The multiplier column is what you pay as a share of the original price.

Discount	You pay	$25 item	$50 item	$100 item	$250 item
10% off	× 0.90	$22.50	$45.00	$90.00	$225.00
15% off	× 0.85	$21.25	$42.50	$85.00	$212.50
20% off	× 0.80	$20.00	$40.00	$80.00	$200.00
25% off	× 0.75	$18.75	$37.50	$75.00	$187.50
30% off	× 0.70	$17.50	$35.00	$70.00	$175.00
40% off	× 0.60	$15.00	$30.00	$60.00	$150.00
50% off	× 0.50	$12.50	$25.00	$50.00	$125.00
60% off	× 0.40	$10.00	$20.00	$40.00	$100.00
75% off	× 0.25	$6.25	$12.50	$25.00	$62.50

Dollars-off coupons vs. percent off

A fixed coupon ("$15 off") is worth more, in percentage terms, on a cheaper item, while a percentage discount grows with the price. Some stores apply a coupon before the percentage discounts and some after, and the order changes the result. With $100, 20% off, and a $10 coupon, taking the coupon last gives $100 × 0.80 − $10 = $70, while taking it first gives ($100 − $10) × 0.80 = $72. This calculator takes the coupon off after the percentages, which is the better outcome for you. If your receipt follows the other order, it will be higher by the coupon amount times the discount rate. To see what percentage a coupon works out to, the percentage calculator answers "$10 is what percent of $40?" (25%).

VAT-inclusive prices outside the US

US shelf prices usually exclude sales tax, which is added at the register. In the UK, the EU, Australia, and many other countries, consumer prices already include VAT or GST. If you're shopping there, leave the sales tax field at 0: the discount applies to the tax-inclusive price, and the tax inside it shrinks in proportion. To see how much VAT a price contains, divide by 1 plus the rate. At the UK's 20% standard rate, a £60 price contains £60 − £60 ÷ 1.20 = £10 of VAT. Businesses that reclaim VAT should discount the net (ex-VAT) price instead. Retailers working out how deep a markdown they can afford should look at the margin calculator, since a 20% discount takes a much bigger bite out of margin than out of price.

Frequently asked questions

How do I calculate 30% off?

Multiply the price by 0.70, since 30% off leaves you paying 70%. A $60 item at 30% off costs $60 × 0.70 = $42, an $18 saving. To do it in your head, find 10% by moving the decimal one place left ($6.00), triple it for 30% ($18), then subtract that from the price. The same trick works for any multiple of 10%.

Is a $10-off coupon better than 10% off?

It depends on the price. 10% off is worth exactly $10 on a $100 purchase, so a $10 coupon wins below $100 and 10% off wins above it. On $40 of shopping, $10 off saves you 25%. On $250, 10% off saves you $25. In general, divide the coupon amount by the percentage (as a decimal) to find the break-even price: $10 ÷ 0.10 = $100.

How do I find the price before tax from a receipt total?

Divide the total by 1 plus the tax rate as a decimal. If you paid $86.40 with 8% sales tax, the pre-tax price was $86.40 ÷ 1.08 = $80.00 and the tax was $6.40. Don't just take 8% off the total ($86.40 × 0.92 = $79.49): tax was charged on the smaller pre-tax amount, so subtracting a percentage of the total removes too much.

How do I work out what percent off I actually got?

Subtract what you paid from the original price, divide by the original price, and multiply by 100. A jacket marked down from $120 to $90 is ($120 − $90) ÷ $120 × 100 = 25% off. Use pre-tax prices on both sides, or tax will make the saving look smaller than it is. The percentage calculator's percent change mode gives the same answer as a negative change.

Do coupons lower the sales tax I pay?

Usually a store's own discount does, because the retailer simply charges less and tax applies to that lower price. Manufacturer coupons are often treated differently. The manufacturer reimburses the store, so many US states tax the price before the coupon. Rules vary by state, so check your receipt. This calculator applies tax to the price after every discount and coupon.