Unit Price Comparator
Enter the price and size of each option — different brands, different pack sizes — to see the price per unit and which one is actually the better deal.
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How to compare unit prices
- Enter the price and size of each option, such as 500 g for £1.20.
- Click + Add item for more options; keep the size unit the same for all.
- The cheapest price per unit is highlighted.
How it's calculated
Price ÷ size gives the price per unit for each item. The lowest price-per-unit is highlighted as the best value — worth double-checking against quality and whether you'll actually use the larger size before it goes bad, since cheapest-per-unit isn't always cheapest overall. Nothing entered here is sent to a server.
Questions about unit prices
How do I work out the price per unit?
Divide the price by the size. 750 ml for £2.25 is 0.3p per ml, or 30p per 100 ml.
Is the bigger pack always better value?
Not always. Multi-buys and offers on smaller packs can beat the big one, which is why it’s worth checking.
Do I need the same units for each item?
Yes. Convert first if one is in grams and another in kilograms, so you compare like with like.
Is the cheapest per unit always the best buy?
Only if you’ll use it all. A big pack that goes off before you finish it can cost more in the end.