Compare the Black Friday price against the item's historical price on price-tracking websites like CamelCamelCamel or Google Shopping. Some retailers inflate prices before Black Friday to make discounts appear larger than they are. A genuine deal should be at or near the item's all-time lowest price.

Many retailers now offer the same prices both online and in-store, though some exclusive doorbuster deals may be limited to one channel. Shopping online lets you compare prices across multiple retailers quickly, while in-store deals may include additional bundle offers. Check both channels for the best price before purchasing.

Absolutely. A 40% discount on an $800 item saves you $320, but 7% tax on the $480 sale price adds $33.60, making the true cost $513.60. Shopping at online retailers that don't charge tax in your state, or in tax-free states, can save you even more. This calculator includes tax so you see the real bottom line.