Compare the price, not the pack
A big pack is not always cheaper, and a sale price on a small one can beat the family size. To know for sure, compare the price for the same amount: per pound, per ounce, per kilo, per liter or per item. Type the two products on lines A and B and the calculator tells you which one is the better deal, and by how much.
How it works
Each price is divided by its quantity, then brought back to a reference unit. For weights in grams and kilos, that is the price per kilo; for volumes in milliliters and liters, the price per liter; for items, the price per item. As soon as one of the two products is in ounces or pounds, both are shown per pound; with fluid ounces, per fl oz. The result is the gap between the two, as a percentage of the dearer one.
Examples
- Grams against kilos. 500 g for $2.40 is $4.80 per kilo; 1 kg for $4.20 is $4.20 per kilo. B is 12.5% cheaper, and saves $0.60 per kilo.
- Ounces. A 16 oz jar for $3.49 against a 24 oz jar for $4.99: $3.49 per pound against $3.33. The big jar is 4.7% cheaper, a smaller gap than the size suggests.
- Ounces against pounds. 12 oz of coffee for $2.99 is $3.99 per pound; a 2 lb bag for $7.50 is $3.75 per pound. The bag is 5.9% cheaper, if you will use it before it goes stale.
- Items. A pack of 6 for $3.60 is $0.60 each; a pack of 9 for $4.95 is $0.55 each. The 9-pack is 8.3% cheaper.
- In pounds sterling. 750 ml of olive oil for £2.25 is £3.00 per liter; 2 liters for £5.40 is £2.70 per liter, 10% cheaper.
Compare like with like
The calculator compares a weight with a weight, a volume with a volume and an item count with an item count. If one line is in grams and the other in liters, it shows a question mark and asks you to compare like with like: a liter of honey does not weigh a kilo, so there is no honest way to convert. If a product is sold by weight on one shelf and by count on another (eggs, rolls, batteries), compare by the item.
Ounces, fluid ounces and liters
An ounce (oz) is a weight; a fluid ounce (fl oz) is a volume. The fluid ounce used here is the US one, 29.57 ml. In the UK, packs are labeled in milliliters and liters, so use ml or liters there. Weights are exact conversions: a pound is 453.59 grams and an ounce 28.35 grams.
Shopping tips
- Check the shelf label. Many stores print a unit price on the shelf tag, but not always in the same unit for two brands. Type both here to put them side by side.
- Multi-buy offers. For “3 for $10”, type 3 items (or the total weight of the three) and $10 as the price.
- Sale prices. Work out the sale price first with the discount calculator, then compare it here.
- Will you use it? A cheaper price per pound only saves money if nothing goes in the bin. Sometimes the smaller pack is the better buy, especially for fresh food, spices or anything that goes stale once opened.
- Cooking for more people. To scale a recipe’s quantities, the proportion calculator does it in one step.
Prices can be in any currency: Currency, in the bottom bar, changes the symbol between $, £, €, C$ and A$, and the choice is kept for the whole site. The result line says how much the cheaper product saves per unit, and Copy result copies the verdict, ready to paste into a shopping list or a message. Reset brings back the example. If you need the percentage difference between two prices without quantities, the percentage calculator does that.