Crunch Unit Price Calculator
Big bag vs small box? Enter both prices and sizes — we'll convert the units and tell you which one is actually cheaper.
Product A
Product B
| Product A unit price | — |
| Product B unit price | — |
| Savings vs the other | — |
How it works
Unit price = price ÷ quantity, converted to a common base unit. Weights convert to ounces (1 lb = 16 oz, 1 kg ≈ 35.27 oz), volumes to fluid ounces (1 gal = 128 fl oz, 1 L ≈ 33.81 fl oz), and counts compare per item. Products must be in the same category (weight, volume, or count) to compare.
Formula & worked example
Formula: Unit price = price ÷ quantity, after both products are converted to a common base — ounces for weight, fluid ounces for volume, items for a count. The lower unit price wins, and the saving is the difference ÷ the higher unit price × 100.
Worked example: Product A at $4.50 for 12 oz costs $0.3750 per oz; product B at $7.00 for 20 oz costs $0.3500 per oz. B wins — 6.7% cheaper per ounce.
Frequently asked questions
What is unit price?
The cost of one unit — one ounce, one liter, one item. Grocery shelves show it on price tags; this calculator does the same math when the units don't match.
What is shrinkflation?
When the package gets smaller but the price stays the same. Unit price exposes it instantly: the "same" $5.99 bag at 14 oz instead of 16 oz costs 15% more per ounce.
Is store brand always cheaper?
Often but not always — sale prices on name brands can beat store brands per unit. Run both through the calculator during the sale and stock up when the unit price is lowest.
🏷️ Stretch every dollar
Pair this with our discount calculator for sale prices.