Interactive tool · works year-round

Price per unit calculator: which size is actually cheaper?

Black Friday bulk packs live or die on the unit math. A bigger box is only a better deal if the price per ounce, per liter or per piece is actually lower — and shelf tags round in the store's favor. Enter your options below and let the conversion math settle it.

How the comparison works

Same-family units convert before comparing: ounces and pounds (and grams, kilograms) are one family; fluid ounces, milliliters, liters, quarts and gallons are another; counts are a third. A 1-liter bottle can compete with a 64-oz jug — but a 1-lb bag of rice will never be ranked against a liter of soda, because the units measure different things.

Unit price pairs naturally with discount math: run the Black Friday price through the stacked discount calculator first, then compare the discounted price per unit here. For multi-item hauls, the shopping list generator prices each line; and if the deal includes a coupon or rebate on top, the stacking simulator shows how the sequence changes the final number.

Conversions use standard unit math on the sizes you enter. Package net weights, fluid contents and count conventions vary by brand — check the label before you buy, and treat unit price as one input alongside quality and how much you will actually use.