Unit Price Comparison Calculator (which size is cheaper per 100 g, ml or item?)

How it works

Unit price = price ÷ size × the base amount you choose (1, 100 or 1,000 units). Enter every size in the same unit — grams with grams, millilitres with millilitres, items with items; convert kilograms or litres first (1 kg = 1,000 g, 1 L = 1,000 ml). The cheapest is the lowest unit price; “cheaper by” compares it with the most expensive one. A bigger pack is only a bargain if you use it all before it spoils.

FAQ

Is the bigger pack always cheaper?

No. Promotions often make a smaller size cheaper per unit, and some large packs cost more per gram. Compare the unit price every time.

What about “2 for 1” or multipacks?

Enter the total price you pay and the total quantity you get, e.g. 2 bottles of 500 ml for 3.00 is size 1000 and price 3.00.

Checked 11 Nov 2026. Unit pricing: price ÷ quantity, the method shelf labels use (e.g. US NIST Handbook 130, Uniform Unit Pricing Regulation). Metric factors: 1 kg = 1,000 g, 1 L = 1,000 ml.