Retailers often raise “regular” prices before sales, so compare with the price history. Multi-buy deals only save money if you would have bought the extra items anyway.
How to use the Black Friday Calculator
- Deal type
- Price per item
- Number of items
- Discount
- Second discount
- Third discount
- Sales tax
- Shipping
Results update as you type, and every field accepts the units shown in its menu.
How it works
Choose the deal type, then enter the price per item, the quantity, the discount(s), sales tax and shipping.
Tips
- Know the difference between margin (profit ÷ price) and markup (profit ÷ cost).
- Apply successive discounts one after another – they do not simply add up.
- Check whether prices already include sales tax or VAT.
- Round prices only at the very end of the calculation.
Common mistakes to avoid
- Adding discount percentages together.
- Pricing from a target margin using the markup formula.
- Forgetting payment-processing and shipping fees.
Inputs explained
| Field | What to enter |
|---|---|
| Deal type | Choose one: Percent off, Percent off the second item, Percent off the third item, Buy one get one free (2 for 1) … |
| Price per item | Amount in your currency |
| Number of items | A number |
| Discount | In % |
| Second discount | In % |
| Third discount | In % |
| Sales tax | In % |
| Shipping | Amount in your currency |
What each result means
- Price without the deal = [Price per item]×[Number of items]
- Total with tax and shipping = [You pay (before tax and shipping)]×(1 + [Sales tax]÷100) + [Shipping]
- You save = [Price without the deal] – [You pay (before tax and shipping)]
- Effective discount = (1 – [You pay (before tax and shipping)]÷[Price without the deal])×100
- Average price per item = [You pay (before tax and shipping)]÷[Number of items]
Example values
How the main result changes when Price per item changes and everything else stays at the example values above:
| Price per item | Total with tax and shipping |
|---|---|
| 40 | 64.2 |
| 60 | 96.3 |
| 80 | 128.4 |
| 100 | 160.5 |
| 120 | 192.6 |
| 160 | 256.8 |
Formula
Percent off: total = price × quantity × (1 − d)X% off the second item: total = price × (1 + (1 − d))Buy N get M free: pay for N of every N + M itemsTotal with tax and shipping = discounted total × (1 + tax) + shippingWorked example
Inputs — Deal type: Percent off; Price per item: $80; Number of items: 2; Discount: 25 %; Second discount: 10 %; Third discount: 5 %; Sales tax: 7 %; Shipping: $0.
Results — Price without the deal = $160.00; You pay (before tax and shipping) = $120.00; Total with tax and shipping = $128.40; You save = $40.00; Effective discount = 25 %; Average price per item = $60.00.
Frequently asked questions
Are Black Friday deals really cheaper?
Often, but some "discounts" are from inflated list prices – check price history.
What is the difference between Black Friday and Cyber Monday?
Black Friday started in stores; Cyber Monday focuses on online deals – both now overlap.
Is buy one get one free the same as 50% off?
Only if you need both items.
What formula does the Black Friday Calculator use?
Percent off: total = price × quantity × (1 − d).