Sticker prices can be deceiving when package sizes differ — a more expensive item can easily be the cheaper option per ounce, gram, or count. Our unit price comparison calculator strips away the package-size variable entirely.
The math
Unit price = Price ÷ QuantityDivide each product’s price by its quantity, and you get a directly comparable cost per unit — per ounce, per gram, per item, whatever unit your quantities are measured in.
Example
A $4.99 16oz bottle versus an $8.49 32oz bottle: the smaller bottle costs $0.3119 per ounce, while the larger one costs only $0.2653 per ounce — making the bigger bottle about 14.9% cheaper per unit, even though its sticker price is higher.
One important rule
Both quantities need to be in the same unit for the comparison to mean anything. If one label lists ounces and the other lists grams, convert one to match the other’s unit first — otherwise you’re not actually comparing like with like.
Cheaper per unit isn’t always the smarter buy
Unit price tells you cost efficiency, not necessarily the best purchase for your situation — factor in whether you’ll actually use up a larger size before it expires or goes stale, your available storage space, and whether a “bulk discount” size is really discretionary spending in disguise.