Enter up to four pack sizes of the same ingredient with their price and size. The tool converts them all to a price per kilo, per litre or per unit, marks the cheapest and tells you how much you save against the dearest. Enter how much you use a month and you also get the monthly saving.
How it works
- Price per kilo or litre = price ÷ size in kilos or litres. Grams and millilitres are converted for you: 500 g is 0.5 kg.
- Price per unit = price ÷ number of units, for eggs, rolls or tins.
- The cheapest is the pack with the lowest price per kilo, litre or unit.
- Saving per kilo or litre = dearest price per kilo − cheapest price per kilo.
- Saving per month = saving per kilo × what you use per month.
If you mix packs in kilos with packs in litres, the tool warns you and does not compare them. To convert measures carefully, see the guide to unit conversions for costing.
Worked example: flour for a small bakery
You get through about 60 kg of plain flour a month for loaves and pastries. You compare three packs:
| Pack | Price | Size | Price per kg |
|---|---|---|---|
| Supermarket bag | $1.89 | 1 kg | $1.89 |
| Larger bag | $6.99 | 5 kg | $1.40 |
| Sack at the wholesaler | $27.50 | 25 kg | $1.10 |
The 25 kg sack is the cheapest. Against the 1 kg bag you save 1.89 − 1.10 = $0.79 a kilo. At 60 kg a month that is 0.79 × 60 = $47.40 a month. The 5 kg bag works out 27.1% dearer than the sack, and the 1 kg bag 71.8% dearer.
Before you decide
- Price per kilo is not everything. A sack is $27.50 out of the till in one go, and a case of oil or a crate of butter can be much more. If you need that cash for this week's dairy order, the saving does not help. The guide to buying in bulk explains how to weigh it up.
- Count what you lose. If a big sack gets damp or weevils get into it, the real price per kilo shoots up. Buy big only what you turn over quickly and can store properly.
- Add the trip. If you drive to the cash and carry only for this, take the fuel and your time off the monthly saving.
From price per kilo to the cost of your recipe
With the price per kilo of the pack you actually buy, you can cost what goes into each loaf or plate. The guide to ingredient cost from the package price shows the sum, and the one on pack size rounding explains what happens when the recipe uses 625 g and the pack holds a kilo. For where the better prices tend to be for your kind of business, see the guide to where to buy.
For the full cost of a product, with ingredients, packaging, your time and the gas, use the food cost calculator.
Frequently asked questions
Is the biggest pack always the best buy?
Not always. It is worth it if you use it before it spoils, have room to store it and can spare the cash on the day. The tool gives you the saving; you decide whether the cash and the shelf space allow it.
Can I compare a pack in kilos with one in litres?
No. A kilo and a litre are not the same thing except for some liquids, and the tool does not guess densities. Compare packs measured the same way: all by weight, all by volume or all per unit.
What do I enter for monthly use?
How much you get through in a normal month, in the same measure as the result: kilos, litres or units. Take it from two or three months of receipts.
Should I count the trip to the wholesaler?
If you make the trip only for this item, yes. Take the cost of the trip off the monthly saving to see whether the bigger pack still pays.