Fast & Simple Price Per Unit Calculator
Quickly compare two items by weight and see the real price per kg, lb or oz
Enter a price and package size to see the price per unit
How this price per unit calculator works
A simple, quick calculator that compares the price of two items per weight — even when one is labeled in grams and the other in ounces. It shows the real price per kilogram, pound or ounce instantly, with a visual bar so the cheaper option is obvious. Works for volume, multipacks and count too.
Why unit price matters
Shelf prices tell you what a package costs, not what the food inside costs. Manufacturers choose package sizes freely — 9 oz, 340 g, 1.36 kg — so two prices side by side rarely compare like with like.
Take shrinkflation: a bag of chips you buy every week shrinks from 10 oz to 9 oz while the price stays at $4.29. The shelf tag looks the same, but you now pay $0.477 per ounce instead of $0.429 — about 11% more. Or the bulk trap: a 16 oz jar on sale for $2.50 costs $0.156 per ounce, while the 40 oz “value size” at $6.99 costs $0.175 — about 12% more per ounce.
Unit price cuts through both. Divide the price by the amount, compare the results, and the cheaper product is obvious — which is what the calculator above does in a second, even when one package is in grams and the other in ounces. Check a product that shrank with the shrinkflation calculator, or read is buying in bulk always cheaper?
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Frequently asked questions
How do I calculate price per ounce?
Divide the total price by the total weight in ounces. For example, a 24 oz box of cereal for $4.79 costs $4.79 ÷ 24 = $0.20 per ounce.
Is bigger always cheaper per unit?
Not always. Sales, shrinkflation, and store-brand pricing mean the medium size sometimes beats the bulk pack. Always compare the per-unit cost, not the shelf price.
What is unit pricing?
Unit pricing is the cost of a product per standard unit of measurement — per ounce, per pound, per liter, or per item. It lets you compare different package sizes on equal footing.
How do I compare prices when packages use different units?
Convert both to the same base unit first. This calculator does it automatically — enter one product in ounces and the other in grams, and it normalizes both.
What is shrinkflation?
Shrinkflation is when a manufacturer reduces the package size while keeping the price the same. The per-unit cost goes up even though the shelf price doesn't change. Compare the price per ounce over time to spot it.
How do I calculate price per pound from price per ounce?
Multiply the price per ounce by 16. If something costs $0.25 per ounce, it costs $4.00 per pound.
What is the difference between ounces and fluid ounces?
Ounces measure weight, fluid ounces measure volume. A fluid ounce of water weighs about one ounce, but for denser liquids like honey the numbers diverge. Don't mix them when comparing prices.
Does this calculator work for metric units?
Yes. Enter package sizes in grams, kilograms, milliliters, or liters. The calculator converts everything to a common base unit for comparison.
Can I compare a product in grams with one in ounces?
Yes. Pick any unit on each product; the calculator converts both and shows the real price per kilogram, pound or ounce.
Does the currency matter?
No. Any currency works as long as both products use the same one — the cheaper item and the percentage stay the same.
How do I compare a 6-pack with one big bottle?
Tap + Multipack, enter 6 × 330 mL, and compare it with the 2 L bottle directly.