Unit Price Calculator

Compare products by price per ounce, gram, litre or item and see which is the better value, with unit conversions, a formula and worked examples.

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Unit price in short
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How to use the unit price calculator

1

Enter the first item

Type the price, the quantity in the pack and the unit, such as ounces, grams or items.

2

Enter the second item

Add the other pack size or brand. The units can differ as long as both measure weight, both volume or both count.

3

Add a third item

Open the advanced section to compare a third product.

4

Read the best value

You get the best value, the price per unit for each item and the saving.

Unit price formula

Unit price formulas

Unit price = total price ÷ quantity

Price per unit in a common unit = price ÷ (quantity × conversion factor)

Saving % = (higher unit price − lower unit price) ÷ higher unit price × 100

Compare unit prices in the same unit. Convert first if the packs use different units.

Common unit conversions for comparing prices
UnitEquals
1 pound (lb)16 ounces, or 453.59 grams
1 kilogram (kg)1,000 grams, or 35.27 ounces
1 gallon128 fluid ounces, or 3.785 litres
1 quart32 fluid ounces
1 pint16 fluid ounces
1 litre1,000 ml, or 33.81 fluid ounces
1 dozen12 items

Unit price examples

Example 1: two box sizes

A 12 oz box costs $4.99 and a 20 oz box costs $7.49.

  • 12 oz box $4.99 ÷ 12 = $0.4158 per oz
  • 20 oz box $7.49 ÷ 20 = $0.3745 per oz
  • Saving with the larger box 9.9%

The larger box is cheaper per ounce, about $5.99 per pound against $6.65.

Example 2: ounces vs pounds

Coffee costs $9.99 for 12 oz, or $17.99 for 2 lb.

  • 12 oz bag $9.99 ÷ 12 = $0.8325 per oz
  • 2 lb bag 2 lb = 32 oz, so $17.99 ÷ 32 = $0.5622 per oz
  • Saving with the larger bag 32.5%

Converting to the same unit is what makes the comparison fair.

Example 3: gallons and fluid ounces

A gallon of milk costs $3.99. A 32 fl oz carton costs $1.09, and a 1 litre carton costs $2.50.

  • Gallon $3.99 ÷ 128 = $0.0312 per fl oz
  • 32 fl oz carton $1.09 ÷ 32 = $0.0341 per fl oz
  • 1 litre carton $2.50 ÷ 33.81 = $0.0739 per fl oz

The gallon is the best value, and the litre carton costs more than twice as much per fluid ounce.

Example 4: price per item

A dozen eggs costs $4.20, and an 18-count carton costs $5.58.

  • Dozen $4.20 ÷ 12 = $0.35 each
  • 18-count $5.58 ÷ 18 = $0.31 each
  • Saving with the 18-count 11.4%

Use the items option for products sold by count.

Why the bigger pack is not always cheaper

Larger packs often have a lower unit price, but not always. Sales, brand and packaging can reverse it, so check the unit price rather than assuming. Buying more also only saves money if you use it before it spoils or expires.

The same idea works for business costs. Divide total cost by units to get cost per unit, then use the markup calculator to set a price, the profit margin calculator to check the margin, or the wholesale pricing calculator for bulk pricing. For sale prices, use the discount calculator and the percentage calculator.

Where a unit price calculator helps

Compare pack sizes

See which size costs less per ounce, gram or litre.

Compare brands

Put different brands on the same unit.

Check a sale

Test whether a deal beats the regular unit price.

Work out cost per item

Divide a bulk price into the cost of one item.

Cheapest is not always best

The lowest unit price only helps if you will use the product. Compare quality, servings, expiry and storage space too. Stores may show their own unit price on the shelf label, which uses their chosen unit.

Unit price calculator FAQ

It is the price of one unit of a product, such as one ounce, one gram, one litre or one item. It lets you compare products sold in different sizes.

Divide the total price by the quantity. A $4.99 box with 12 oz costs $4.99 ÷ 12 = $0.4158 per ounce.

Use price ÷ quantity. For several items, convert them to the same unit first so the results can be compared.

Divide the price by the number of ounces. If the pack is in pounds, multiply the pounds by 16 first.

Convert them to a common unit. For example, 1 lb is 16 oz and 1 gallon is 128 fluid ounces. The calculator does this for you.

No. Ounces measure weight and fluid ounces measure volume, so they are not interchangeable. Compare items measured the same way.

No. Larger packs are often cheaper per unit, but sales and brands can change that. Check the unit price.

Divide the total cost by the number of items. A $5.58 carton of 18 eggs costs $0.31 each.

It is the total cost of making or buying a product divided by the units produced or bought. It is the starting point for setting a price.

It is the difference between the higher and lower unit price, divided by the higher unit price, shown as a percentage.

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Estimates, not advice

PureCalculate’s calculators give estimates for planning and education. They aren’t financial, tax or legal advice. Fees and tax rules change, so check the official source before making a decision. Spotted a mistake? Please tell us through the contact page.

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