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Unit price calculator
Compare up to five products by the amount you actually get. Convert pounds to ounces, liters to fluid ounces, or compare items in multipacks, with discounts and checkout costs included.
- Weight, volume or count
- Values stay in your browser
Compare your options
Enter the checkout price and package size for each option.
Unit price comparison
All options are converted to cost per oz.
Lowest unit price
1 lb pack
$0.1250 / oz (25.0%) below the next cheapest option
- 8 oz pack$0.5000 / oz
$4 total after discount, shipping and tax
- 1 lb pack$0.3750 / oz
$6 total after discount, shipping and tax
Transparent math
How to calculate price per unit
Unit price = (price after discount + shipping + tax) ÷ (size per pack × number of packs). The calculator converts each size to the same base unit before dividing, then shows the result in your chosen unit: grams, kilograms, ounces, pounds, milliliters, liters, US fluid ounces, US gallons or items.
Example: an 8 oz pack at $4 is $0.50 per oz. A 1 lb pack at $6 contains 16 oz and costs $0.375 per oz; the larger pack is 25% cheaper per ounce. One pound is exactly 16 avoirdupois ounces. A fluid ounce measures volume and cannot be compared with a weight ounce without density.
Compare multipacks with a single package
A $12 pack containing six 250 g bags contains 1.5 kg in total, so it costs $8 per kg. A single 1 kg bag at $9 costs $9 per kg. Enter the total multipack price once, then enter 6 packs and 250 g per pack; do not multiply the price by six again.
Does a discount make the larger pack cheaper?
Apply the discount to the item price, then add the shipping and tax you expect to pay. A $10 package with a 10% discount and $3 shipping still costs $12 delivered. The cheapest shelf price can therefore have a higher final unit cost.
Which ounces and gallons does this use?
Weight uses avoirdupois ounces and pounds. Volume uses US liquid measures: one US fluid ounce is 29.5735295625 ml and one US gallon is 3.785411784 liters. These are different from Imperial fluid ounces and gallons. Switch to liters or milliliters for a metric comparison.
Included in this comparison
- 2–5 options in one comparison
- Choose the result unit, including cost per kilogram or liter
- Multipack quantities and percentage discounts
- Your own shipping and tax amounts, plus CSV export
Know the boundary
Compare like with like
Weight, volume and item count are separate comparisons. Shipping and tax are entered by you; this tool does not infer a local tax rate, product density, or quality difference. Prices use USD.
Next calculation
Work out your break-even point
If you sell products, take your unit cost into the break-even calculator to see how many sales cover your fixed costs.