What do I put for 'size'?

Any consistent measure for both — ounces, count, grams, sheets. As long as A and B use the same unit, the comparison is valid.

Why isn't bulk always cheaper?

Retailers know shoppers assume it is, so the larger size sometimes has a higher unit price. This catches it.

Calculators › Everyday Money Decisions › Unit Price Comparison Calculator

Calconomics

Unit Price Comparison Calculator

Bigger isn't always cheaper. Enter the price and size of two options to see the real cost per unit and which is the better buy — the answer surprises people in the grocery aisle constantly.

Option A

Option A — price

Option A — size/count

Option B

Option B — price

Option B — size/count

Better deal

Option A is the better value

Option A — per unit

$0.25

Option B — per unit

$0.33

The numbers

Better option is cheaper by

25.00%

US$3.99 · download & own it forever

Prices in

How it's calculated

Unit price = price ÷ size (ounces, count, grams — just be consistent).
The lower unit price is the better value.
We also show how much cheaper the winner is, as a percentage.

Our methodology & 2026 data sources →

Frequently asked questions

What do I put for 'size'?: Any consistent measure for both — ounces, count, grams, sheets. As long as A and B use the same unit, the comparison is valid.
Why isn't bulk always cheaper?: Retailers know shoppers assume it is, so the larger size sometimes has a higher unit price. This catches it.