01
How to use this calculator
- Choose whether you are comparing weight, volume or item counts.
- Enter the total price, size of one item and number of items in each pack.
- Compare the normalized prices. The highlighted option has the lowest cost per unit.
02
A little understanding goes a long way.
Savings compare each option with the cheapest option, using the more expensive option as the baseline.
THE FORMULA
Unit price = total price ÷ total quantity
TRY IT ON PAPER
A worked example
A 500 g bag costs $4.50. A 750 g bag costs $6.00. Their prices per kilogram are $9.00 and $8.00, so the larger bag costs 11.11% less per kilogram.
03
A few common questions
Can I compare grams with pounds?
Yes. Select Weight and use the appropriate unit for each option. Results are normalized to kilograms. Volume comparisons use litres, and counts use individual items.
Does a lower unit price always mean a better purchase?
Not necessarily. Consider quality, storage, expiry dates and how much you will actually use. This tool compares quantity and price only.
Are currencies converted?
No. The currency selector changes the display symbol only. Enter every price in the same currency and include applicable discounts consistently.