Black Friday Deal Calculator 2026

The Black Friday Deal Calculator 2026 shows what you will actually pay for something in the Black Friday and Cyber Monday sales, and whether the deal is as good as it looks. Enter the list price and the Black Friday discount (or just the sale price), then add any extra coupon code, an extra percentage taken off at checkout, a fixed-amount coupon, shipping, your cashback or card rewards and your state's sales tax. It instantly shows the final price, how much you save in money and as a percentage, the true combined discount and your effective cost after cashback. It also checks the sale price against the item's usual price and its lowest price in the last 90 days, compares the same item at up to three stores and totals a whole Black Friday shopping list against your budget. In 2026 Black Friday falls on Friday 27 November and Cyber Monday on Monday 30 November.

Stacked discounts multiply rather than add, which is why the calculator shows a "true combined discount". A 40% Black Friday discount plus an extra 20% coupon is not 60% off: the coupon comes off the already-reduced price, so you pay 0.60 × 0.80 = 48% of the list price, a real discount of 52%. The general formula is final item price = price × (1 − discount) × (1 − coupon) × (1 − extra) − fixed coupon. Sales tax is then charged on that discounted price, shipping is added, and cashback is subtracted at the end to give your effective cost.

Worked example: a $500 TV is 30% off for Black Friday and you have an extra 15% coupon, 5% cashback and you live in California (7.25% state sales tax). The sale price is $500 × 0.70 = $350, the coupon brings it to $350 × 0.85 = $297.50, and sales tax adds $297.50 × 7.25% = $21.57, so you pay $319.07 at checkout. Cashback of 5% on $297.50 returns $14.88, for an effective cost of $304.19. You save $202.50 on the item, a true combined discount of 40.5%, not the 45% you might expect from adding 30% and 15%. Compared with paying full price plus tax ($536.25), you are $232.06 better off once cashback is counted. Local taxes in many California cities would add a little more.

Not every Black Friday discount is a real one. Some "was" prices are inflated, or the item was just as cheap a few weeks earlier. That is why the deal check asks for the item's normal price and the lowest price seen in the last 90 days, which you can read off a price tracker or the store's price history. If the Black Friday price is clearly below that 90-day low it is a genuine deal; if it matches the low it is simply the usual sale price; and if it is higher you could have paid less before. In the US, the FTC's Guides Against Deceptive Pricing (16 CFR Part 233) say a former price should be one at which the item was genuinely offered for a reasonably substantial period, not an inflated figure set up to make a discount look bigger. In the UK, misleading pricing is a banned unfair commercial practice under the Digital Markets, Competition and Consumers Act 2024, which the CMA has enforced directly since 6 April 2025.

Sales tax rules matter too. In the US, sales tax is normally charged on the price after store discounts and store coupons, so a bigger discount also means less tax. Manufacturer coupons are different in many states (New York, for example, charges tax on the full price before a manufacturer's coupon), and whether shipping is taxable varies by state, so the calculator lets you choose. The state dropdown pre-fills the 2026 state base rate from the Tax Foundation; add your local rate for an exact figure. In the UK and EU, shop prices already include VAT, so choose the "Prices include VAT" mode and no tax is added on top.