How to use this calculator
- Enter the regular price of one item.
- Enter how many items you pay for and how many you get free.
- Check the effective discount, total paid, and price per item.
Example: Buy 3, get 1 free
Suppose each item normally costs $5. You pay $15 for three items and receive four items in total. Buying four at regular price would cost $20, so you save $5 and pay an effective price of $3.75 per item.
One out of the four items is free, so the promotion is equivalent to 25% off.
Effective discount formula
Use free items ÷ (paid items + free items) × 100. Buy one, get one free is 50% off. Buy two, get one free is about 33.33% off. Buy four, get one free is 20% off.
Frequently asked questions
Does “buy 3, get 1 free” mean I receive four items?
Usually, yes: you pay for three and receive one additional item free. Always check the promotion's wording and eligible items.
What if the items have different prices?
This calculator assumes every item has the same regular price. Some promotions make the lowest-priced item free, so use the actual receipt total when prices differ.
Is a bulk promotion always worth it?
No. The effective discount only helps if you need the full quantity. Storage, expiration dates, and purchase limits may change the practical value.