Price Per Unit Calculator
Compare items by price per kilo, litre, metre or item and see instantly which pack size is the better deal.
Enter a price and a pack size for at least two items — the cheapest per unit is worked out as you type.
| # | Item | Price | Total size | Unit price | Vs best |
|---|
How it works
Unit price is one division: unit price = total price ÷ total quantity. The
calculator first turns every pack into one common base unit — grams for weight, millilitres
for volume, metres for length, single items for a count — using exact conversion factors
(1 lb = 453.59237 g, 1 oz = 28.349523125 g, 1 US fl oz = 29.5735295625 ml, 1 US gallon =
3785.411784 ml, 1 in = 2.54 cm). Total quantity is packs × size each, so a
6 × 330 ml multipack is 1,980 ml. Then it converts back to whatever you chose in "Show price
per", so a $3.50 bag of 500 g comes out at $7.00 per kg and a $5.00 bag of 800 g at
$6.25 per kg.
Items are ranked cheapest first, the winner is flagged as best value, and every other item
shows how much more it costs per unit — (unit price − best) ÷ best as a
percentage. $7.00 per kg against a best of $6.25 per kg is 12.0% more expensive. Compare up
to six items, mix units freely inside one family (grams against pounds, millilitres against
fluid ounces), then copy the comparison or download it as CSV. Everything is plain arithmetic
in your browser: nothing is uploaded, there is no sign-up and there are no ads.
Frequently asked questions
How do you calculate price per unit?
Divide the total price by the total quantity: unit price = price ÷ quantity. The calculator turns every pack into one base unit first (grams, millilitres, metres or single items) using exact factors — 1 lb = 453.59237 g, 1 oz = 28.349523125 g, 1 US fl oz = 29.5735295625 ml — and multiplies packs × size each, so a 6 × 330 ml multipack counts as 1,980 ml. A $3.50 bag of 500 g works out at $7.00 per kg.
Which pack size is cheaper?
Enter each option as its own item and the tool ranks them cheapest first, flags the winner as best value and shows how much more every other option costs per unit. A $5.00 bag of 800 g is $6.25 per kg, so the $3.50 bag of 500 g at $7.00 per kg is 12.0% more expensive per kilo — the bigger bag wins even though it costs more at the till. Bigger is not always cheaper, which is exactly what this check is for.
Can I compare different units, like grams and pounds?
Yes. Pick the family you are measuring (weight, volume, count or length) and each item can use any unit inside it — grams against pounds, millilitres against US fluid ounces, metres against feet. Choose what the answer should be expressed in with "Show price per", such as per kg, per 100 g, per litre or per item. Everything is computed locally in your browser, and you can copy the comparison or download it as CSV.