How to use the Unit Price Calculator
- Enter each product's price and size.
- Pick each product's unit — they can differ (e.g. grams vs kilograms).
- See which is cheaper per unit, and by how much.
What does this tool do?
Bigger packs aren't always cheaper per unit, and different units make comparisons hard. The calculator converts both products to the same base unit (grams, millilitres or items) before comparing.
Why use it?
- Compares across units, like ounces against grams.
- Shows the price per kg, litre or item.
- Shows how much cheaper the better option is.
Example
500 g of coffee for $4.99 works out to $9.98 per kg. A 1 kg bag for $8.49 is $8.49 per kg, so the bigger bag is about 15% cheaper per kilogram.
The formula
Privacy
The calculation happens instantly in your browser. The numbers you enter are not sent to our servers or saved. There's no account to create and nothing to install.
Frequently asked questions
Is the bigger pack always the better deal?
No. Multi-buys and large packs are sometimes more expensive per unit than the standard size, especially when the smaller one is on offer. Comparing unit prices is the only reliable way to tell.
Should I always buy whatever is cheapest per unit?
Only if you'll use it all. A cheaper-per-kilo bag that goes off before you finish it costs more in the end. Unit price is the best comparison for things that keep, like rice, detergent or toilet paper.
Last reviewed by the M2Toolkit team.