How to use the bogo discount calculator
- Enter the price of one item. The offer is figured as if every item costs the same.
- Set the terms: how many items you pay full price for, how many you get at a discount, and the percent off those items. Buy one get one half off is 1, 1 and 50%.
- Enter how many items you plan to buy. Items that do not complete a set are charged at full price.
- Read what you pay, what you save and the effective discount across everything you buy.
Formula
Set size = items you pay for + items you get discounted
Complete sets = whole number of (items bought / set size)
Discounted items = complete sets x discounted items per set
You save = price x discounted items x discount %
Effective discount = savings / (price x items bought) x 100%
Free items use a discount of 100%. Leftover items that do not make a full set are charged at the full price.
Buy one, get one 50% off on a $20 item
A set is 1 + 1 = 2 items. For two items at $20, one is full price and one is half price, so you pay $20 + $10 = $30 instead of $40. You save $10, an effective discount of 25% on everything, and each item averages $15.
Buy two, get one free on $12 items works out differently. Three items cost $24 instead of $36, a saving of $12 or 33.33%. If you buy five, there is one complete set and two leftover items at full price, so you pay $48 instead of $60 and the effective discount falls to 20%.
Why 50% off the second item is not 50% off
A buy one get one half off offer takes 50% off only one of every two items, so the saving across the pair is 25%. Buy one get one free is 50% off overall, and buy two get one free is about 33%.
The effective discount depends on how many items you take. Buying an odd number leaves an item at full price and lowers the overall saving, so the number of items you plan to buy matters.
Checking the offer terms
Stores handle mixed prices in different ways. Many discount the cheaper item, some apply the discount to an item you choose, and some limit the number of sets or exclude certain products. Read the terms before you plan a purchase around one.
To compare a deal with a plain percent off use the discount calculator or the coupon vs percent off calculator. When pack sizes differ, the unit price calculator shows which product costs less per ounce or per item.
Assumptions and limits
- Every item costs the same price.
- Discounts are applied to whole sets of items in the order you enter, and leftover items cost full price.
- Sales tax, shipping and loyalty rewards are not included.
- A discount of 100% means free, and the tool does not limit the number of sets.
Frequently asked questions
What is the discount on buy one get one half off?
It is 25% across the two items. You pay full price for one and half price for the other, so the pair costs 75% of the full price.
How much is buy two get one free?
Three items cost the price of two, so the saving across the set is one third, or 33.33%, when all three items cost the same.
Does it matter how many items I buy?
Yes. Only complete sets get the discount. With a two-item offer, three items give one discounted item and leave one at full price, so the effective discount is lower than for four items.
Is a BOGO deal always better than a percent off?
No. Compare the effective discount from this tool with the percent off on offer, and look at unit prices if the products differ. A deal only helps if you would use everything you buy.