Unit Price Calculator
Compare price per unit, ounce, pound, gram, item, or package across different products.
Item A
Item B
Better Value
Store Brand
saves 8.9% per oz ($0.0107/unit)
Store Brand — per oz
$0.1091
Name Brand — per oz
$0.1197
These results are estimates for informational purposes only. Actual costs may vary.
What this calculator tells you
A larger package is not always the better deal. This calculator helps you compare the true price per unit across different sizes, quantities, and brands so you can see which option costs less.
Issues With calculators are deterministic tools, not AI guesses. Your result is calculated from the numbers you enter using the formula shown below, and the inputs stay in your browser.
How this calculator works
Enter the price and quantity for two items — same product in different sizes, or two competing brands. Use the same unit for both to get a fair comparison. The calculator instantly shows the price per unit for each and highlights the better value.
Works for any quantity-based comparison: ounces of food, rolls of toilet paper, count of tablets, liters of detergent, and more. If you enter different units, the calculator will flag it so you don't compare apples to oranges.
The formula
Unit Price A = Price A ÷ Quantity A
Unit Price B = Price B ÷ Quantity B
Better Value = lower unit price
Savings per Unit = |Unit Price A − Unit Price B|
Savings % = (Savings per Unit ÷ Higher Unit Price) × 100
Example
Comparing two laundry detergents:
- Store brand: $7.49 for 64 oz = $0.1170/oz
- Name brand: $11.99 for 75 oz = $0.1599/oz
The store brand is the better value — 26.8% cheaper per ounce, saving $0.0429/oz despite having a lower sticker price and smaller bottle.
Frequently asked questions
Is the biggest package always the best deal? +
Not always. Retailers sometimes price smaller packages at a lower per-unit cost to move inventory, or run promotions that make mid-size the winner. Always check the unit price rather than assuming bigger = cheaper.
What if quality is different between items? +
This calculator compares only price per unit — quality, ingredients, and effectiveness are factors you'll need to weigh separately. A lower unit price isn't always the right choice if the product is inferior.
Do grocery stores show unit prices on shelf tags? +
Most US retailers are required to display unit prices on shelf tags. However, they sometimes use different units for similar products (e.g., one in oz, one in count) — which is exactly when this calculator is most useful.
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