Unit Price Formula
Best Value = Lowest Unit Price
When to Use Unit Price
- Grocery shopping: Compare a 12-oz can for $1.29 vs a 28-oz can for $2.49 — which is cheaper per ounce?
- Bulk buying: Is the warehouse club 48-pack worth it vs the 12-pack at the regular store?
- Different pack sizes: 6-pack vs 12-pack vs 24-pack of the same product
- Sale vs regular price: Does a "buy 2 get 1 free" deal beat the competitor's everyday price?
Real Examples
| Product | Price | Size | Unit Price | Best? |
|---|---|---|---|---|
| Brand A | $1.29 | 12 oz | $0.1075/oz | |
| Brand B | $2.49 | 28 oz | $0.0889/oz | ✅ Best |
| Store Brand | $1.89 | 20 oz | $0.0945/oz |
Frequently Asked Questions
Is the larger size always cheaper per unit?
Not always. Retailers sometimes price smaller sizes more competitively, especially during sales. Store brands in mid-sizes often beat large name-brand sizes. Always check the unit price label on the shelf (required in many US states) or use this calculator to verify.
What units should I use?
Use consistent units across all items you compare. You can use any unit — ounces, grams, litres, count, sheets, etc. — as long as you use the same unit for all items in the comparison. This calculator shows unit price as price-per-one-unit of whatever quantity you enter.
Does unit price account for quality differences?
No — unit price is purely a price comparison tool. Quality, freshness, taste preferences, and brand loyalty are separate considerations. Unit price tells you the most economical option but not necessarily the best overall value for your specific needs.