Unit Price Comparison Calculator

How it is calculated

For each product the tool divides the price by the quantity: unit price = price ÷ quantity. Products A and B each have a price in dollars and a quantity in any unit you choose, such as ounces, grams, sheets or items. The tool compares the two and reports which product is cheaper per unit, or Equal when the unit prices match. The comparison uses the exact figures (price A × quantity B against price B × quantity A), not the rounded ones, and treats differences far below a cent's fraction as a tie. It does not convert units, so both quantities must be in the same unit: 500 g and 1 kg cannot be mixed. Unit prices are displayed rounded to cents, so for goods that cost a fraction of a cent per unit the displayed figures can look identical even when one is cheaper; scale the quantity, for example compare per 100 g. Each quantity must be above zero and a price cannot be negative (0 is accepted), otherwise there is no result.

Common mistakes

• Mixing units, for example 500 g for A and 1 kg for B. The tool divides blindly, so convert both to grams (or both to kilograms) first.
• Entering the number of packs instead of the amount inside one pack. A 6-pack of 330 ml cans is 1,980 ml, not 6.
• Trusting the rounded unit prices alone. Two products can both display $0.00 per unit while one is cheaper, and the tool still names the right one, but you will not see the gap until you use a larger base unit such as 100 g.
• Ignoring the part of a big pack you will not use or that will spoil. The lower unit price only pays off if you use all of it.
• Comparing a sale price with a regular price. Enter the price you actually pay for each product at checkout.