How to use
- Enter the shelf price and the quantity for option A. Quantity is the number of units you will compare, such as ounces or counts.
- Enter the same kind of quantity for option B.
- Press Calculate. The hero number is the cheaper unit price.
- If the result looks backwards, check that both quantities use the same unit.
How it's calculated
Unit price = package price ÷ quantity. The comparison subtracts the two unit prices. The smaller unit price wins. Equal unit prices, within a fraction of a cent, are reported as a tie.
The page does not convert ounces to pounds or counts to liters. Convert first if the labels use different units. The unit converter on this site does length, weight, volume, and temperature.
Worked example
Three items for $5 cost about $1.67 each. Ten items for $14 cost $1.40 each. Option B is cheaper by about $0.27 per item. The ten-pack costs more at the register and still wins on unit price.
Assumptions
Two packages, one unit shared by both quantities. No coupon unless you already subtracted it from the price you typed. No tax.
FAQ
What if one label is ounces and the other is pounds?
Convert both to the same unit before you type the quantities. This page will not guess.
Does a lower unit price mean I should buy more?
Only if you will use what you buy. The math does not know spoilage or storage.
Can quantity be a weight?
Yes. Type the weight as the quantity and use the same weight unit on both options.
Why did it call a tie?
The unit prices match after ordinary rounding. A fraction of a cent is treated as the same price.