Unit Price Comparison Calculator (Better Buy)
Compare two product sizes or package options by price per unit to find which one is actually the better deal.
- Option A — price per unit
- 0.3119
- Option B — price per unit
- 0.2653
- Better deal
- Option B is the better deal (14.9% cheaper per unit)
How it works
A larger package isn't automatically the better deal — this divides each option's price by its quantity to get a price per unit, then compares the two directly: unit price = price ÷ quantity. Whichever option has the lower price per unit is the better buy, and the savings is expressed as a percentage of the pricier option's unit price.
This only works correctly if both quantities are entered in the same unit — both in ounces, both in a count of items, both in milliliters, and so on. The calculator doesn't know or convert between units, since the whole comparison depends on you supplying a consistent one for both options.
FAQ
Why isn't the bigger package always the better deal?
Retailers don't price package sizes proportionally — a larger size is often, but not always, cheaper per unit, and "bulk" pricing sometimes carries a premium instead of a discount. Comparing the actual price-per-unit is the only way to know for a specific pair of options, rather than assuming size correlates with value.
What if the two options are priced in different units, like ounces vs. milliliters?
Convert one of them to match the other's unit first (see this site's Weight or Volume unit converters), then enter both quantities in that same shared unit here — mixing units would silently produce a meaningless comparison.