How to Compare Unit Prices
Make a fair comparison between different package sizes.
What it does and when to use it
Package price is misleading when quantities differ. Unit price puts both options on the same basis.
What information to enter
Enter price and quantity for each product using the same unit—grams with grams or liters with liters.
How to understand the result
The lower price per matching unit is cheaper when quality and usefulness are comparable.
Recommended step-by-step workflow
- Check the assumptionsPackage price is misleading when quantities differ. Unit price puts both options on the same basis.
- Use matching unitsEnter price and quantity for each product using the same unit—grams with grams or liters with liters.
- Compare with another scenarioThe lower price per matching unit is cheaper when quality and usefulness are comparable.
Formula at a glance
Unit price = total price ÷ quantity
Short example
$18 for 750 g is $0.024/g; $22 for 1 kg is $0.022/g and therefore cheaper.
Common mistakes
- Comparing 750 g with 1 kg without unit conversion.
- Buying excess that will be wasted only because unit price is lower.
Frequently Asked Questions
Can I compare a buy-two-get-one offer?
Yes. Use total paid and total quantity after the offer.
What about quality?
The calculator compares price only; quality, shelf life, and convenience also matter.
Are my personal inputs saved?
No. The calculators and guides are designed for quick browser use without storing your personal input values.