Ecommerce
Buy One Get One Calculator
Enter item price and deal pattern (e.g. buy 1 get 1 free) to see effective unit price.
Effective price on BOGO deals
BOGO means “buy one get one” (or a similar pay-N-get-M pattern): you pay for N items at list price and receive M items in total. Effective unit price = (N × price) ÷ M, and the headline discount versus paying full price for all M items is easy to overstate in marketing copy. Classic “buy one get one free” on a £20 item is £10 effective per unit — 50% off the pair, not “100% off” in accounting terms. Enter item price, items paid for and total items received to compare with a straight percent-off banner. Exclusions and “cheapest free” till rules are approximated by the pay/get counts you enter. Cross-check margin with product profit and voucher-style cuts with coupon profit.
Worked example
Buy 1 get 1 free on a £20 item: pay £20 for 2 received → £10.00 effective unit price, 50% effective discount, £20 saved vs buying both at full price.
Limits and assumptions
Ignores brand exclusions, stacking with other codes and till rules beyond the pay/get counts you enter.
Frequently asked questions
What does BOGO stand for?
Buy one get one — usually “buy one get one free” or a variant where you pay for some items and receive more.
How do I model buy 2 get 1 free?
Set items you pay for to 2 and total items received to 3.
Is BOGO better than 50% off a single item?
Compare effective unit prices. BOGO 50% off two units is not the same shopping decision as 50% off one unit.
How do I check margin after a BOGO?
Use the effective unit price as the selling price in a product-profit calculation against your unit cost.