How unit price comparison works
This tool compares the price-per-unit of several product options so you can tell which size or pack is the best value for money, not just the cheapest sticker price. For each option you enter the price and the quantity (size), plus the unit it is measured in. The calculator divides price by the quantity, converted to a shared base unit, to give a fair price-per-unit that works even when the packs use different units.
Units are grouped into three categories: mass (grams, kilograms, ounces, pounds), volume (milliliters, liters, fluid ounces, cups, pints, quarts, gallons), and count (each). Each unit is converted to its category's base unit (gram, milliliter, or each) using standard conversion factors, so a 12-ounce can at $3.99 and a 750-milliliter bottle at $5.49 can be compared on a like-for-like basis. All items in one comparison must belong to the same category, because a price per gram cannot be meaningfully compared with a price per milliliter.
The option with the lowest price-per-unit is flagged as the best value. Everything runs in your browser with no data sent anywhere, so it works offline and keeps your shopping list private. Bulk and family packs often win on price-per-unit, but not always after you factor in waste or perishability this tool cannot measure.