Black Friday Deals Calculator
Enter the sticker prices and the advertised discount to find out whether the deal is real or inflated — then stack extra codes, add tax and shipping, and see your true savings. Updated for Black Friday 2026 (Nov 27).
1 · Enter the deal
2 · Is it a real deal?
Enter prices to check the deal
Add the "was" price and sale price above and we will verify the advertised discount.
Black Friday deal math — FAQs
How do I check if a Black Friday deal is real?
Take the original ("was") price and the sale price, then calculate (was − sale) ÷ was × 100. That is the true discount percentage. Compare it with the advertised percentage on the badge — if they differ by more than about 1 point, the claim is inflated and the "was" price was likely raised.
Why is 20% off plus an extra 10% code not 30% off?
Stacked discounts are multiplicative, not additive. A 20% discount followed by a 10% coupon gives 1 − (0.80 × 0.90) = 28% off in total, because the second discount applies to the already-reduced price. Our calculator shows the true stacked rate.
How do retailers inflate "was" prices on Black Friday?
Some stores raise the reference price shortly before the sale, or compare against a rarely-charged list price, so the percentage looks bigger. Check the product's price history and compare the sale price across at least two other stores before you buy.
Should I include tax and shipping when comparing deals?
Yes. Two deals with the same discount percentage can have very different final costs once sales tax or VAT and shipping are added. Always compare the all-in order total, not just the headline discount.
When is Black Friday 2026?
Black Friday 2026 falls on Friday, November 27, 2026, with Cyber Monday on November 30, 2026. Many retailers now run deal weeks starting up to two weeks earlier, so the math above works for early-bird deals too.
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