Unit Price Calculator

Unit Price Calculator

Unit Price Calculator compares products by cost per unit so you can tell which package is actually cheaper. Add as many products as you want and set the unit label to whatever you are measuring in.

How to use it

1. Set the unit label to match what you are comparing: oz, kg, sheets, litres, whatever fits.
2. Add each product with its price and its size.
3. Read the cost per unit for each and compare directly.

Why bigger is not always cheaper

Unit price is simply the total price divided by the quantity. It is the only number that lets you compare a 12 ounce jar against an 18 ounce jar at different prices.

Retailers know shoppers assume the large size is better value, and it often is not. Comparing per unit is the only reliable check, and shelf labels frequently use inconsistent units between competing brands to make it harder.

When it helps

• Grocery shopping where the same product comes in three sizes.
• Comparing bulk purchases against buying as you go.
• Checking whether a multi-buy offer is genuinely cheaper per item.
• Comparing two brands that package in different quantities.

Common mistakes

• Comparing across different units without converting. A price per litre and a price per fluid ounce cannot be compared directly.
• Ignoring waste. The cheapest unit price is not a saving if you throw half of it away.
• Trusting the shelf unit price without checking. They are frequently wrong or use a different unit than the product beside them.