Unit Price Calculator

Which is the better deal — the big box or the small one? Enter the price and quantity for two options and this shows the price per unit for each, which one wins, and by how much. Beat misleading package sizes in seconds. Updates as you type.

How to use it

price per unit = price ÷ quantity

• Use the same unit for both options — both in grams, both in ounces, and so on.
• The lower price per unit wins, even if its sticker price is higher.
• Watch multipacks and "specials" — they're often not the cheapest per unit.

An educational comparison tool. It doesn't account for whether you'll actually use the larger quantity before it expires. Not financial advice.

FAQ

How do I calculate price per unit?

Divide the price by the quantity in the package. A $4.50 bag of 500 g costs 4.50 ÷ 500 = $0.009 per gram. Comparing the price per unit — not the package price — tells you which size or brand is actually cheaper.

Why is the bigger package not always cheaper per unit?

Retailers price packages to look like deals, but the per-unit cost can be higher on the larger size, on multipacks, or on a "special". The only reliable way to compare is price per unit, which this calculator works out for both options instantly.

Do both products need the same unit?

Yes — enter both quantities in the same unit (both in grams, or both in ounces, etc.) so the comparison is fair. Convert first if one is listed in grams and the other in kilograms, for example.

What can I compare with this?

Anything sold in different sizes or quantities: groceries (per gram, ounce, litre), household goods (per sheet, per wash), bulk vs single items (per item), or any two prices where you want the true cost per unit.

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