One product
Normalize a pack price to a useful shopping unit.
- Price is the total offer price. Use the same currency throughout.
Shopping & Household calculator
Unit Price & Offers
Compare equivalent quantities across pack sizes, bulk purchases and multibuy offers without mixing incompatible units.
What does a worked calculation look like?
500 g for 3.00 is 6.00 per kg (0.60 per 100 g). 750 g for 4.65 is 6.20 per kg. The smaller pack is cheaper by 0.20 per kg, a saving of about 3.2%, and buying 500 g of the larger product would cost 3.10.
Method and practical checks
- Price is the total offer price. Use the same currency throughout.
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Every calculation option
Compare products
Compare two offers on the same mass, volume or item basis.
- Bulk and multibuy offers use the total price and number of identical items in that offer.
- Mass cannot be compared with volume without a product-specific density; this tool rejects that comparison.
- A lower unit price saves money only if you use the quantity purchased.
Worked example
500 g for 3.00 is 6.00 per kg (0.60 per 100 g). 750 g for 4.65 is 6.20 per kg. The smaller pack is cheaper by 0.20 per kg, a saving of about 3.2%, and buying 500 g of the larger product would cost 3.10.
| Input | Value |
|---|---|
| Price | 3 |
| Quantity per item | 500 |
| Unit | g |
| Items in offer | 1 |
| Result | Value |
|---|---|
| Product A unit price | 6 / kg |
| Product A price per 100 g | 0.6 |
Reading the result
- A lower unit price only saves money if you use the extra quantity before it spoils or you lose interest.
- Mass and volume cannot be compared without the product’s density, so the calculator rejects that comparison.
- For multibuy offers, enter the total price and the number of identical items in the offer.
Sources and further reading
- NIST Guide to the SI, Appendix B.8 (conversion factors) — Exact yard, pound and ounce factors and the US cup (236.5882 mL).
How do I compare different pack sizes?
Divide each price by its total quantity in the same base unit, including all items in a multi-pack. A 500 g pack at 3 costs 6 per kg, while a 1 kg pack at 6.20 costs 6.20 per kg. The larger pack is not automatically cheaper.
Can I compare price per litre with price per kilogram?
Only when you know the product's relevant density and deliberately convert the quantities. The ordinary comparison modes keep mass, volume and item counts separate. Choose compatible units so that the displayed lower unit price represents a meaningful comparison between the products.
Does the lowest unit price always mean the best purchase?
No. The result compares quantity and price under the stated inputs. Consider how much you will use, storage, expiry, quality and your cash outlay. A discounted larger pack can waste money if much of it is discarded before use. Check usable stock too. Check usable stock too.
Calculation/content reviewed 4 October 2026. Source: Babushka Market’s displayed formulas, units and labelled editable assumptions. How the estimates work