Price Per Unit Comparison Calculator

Compare two products by unit price to see which is genuinely the better deal, regardless of package size.

Product A Price ($)

Product A Size (units)

Ounces, grams, count, or any unit — just use the same unit for both.

Product B Price ($)

Product B Size (units)

Use the same unit you used for Product A.

Results update as you type.

Product A Unit Price

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Product B Unit Price—

Better Deal—

How it works

A price per unit comparison calculator settles the everyday shopping question of which product is truly cheaper when two options come in different sizes. Shelf prices are designed to be hard to compare — a larger bottle may cost more in total yet less per ounce, while a 'value' size occasionally costs more per unit than the standard one. Reducing both to a price per unit removes the guesswork and reveals the genuine better deal. The method is straightforward: divide each product's price by its size to get the cost of one unit, then compare. As long as you measure both in the same unit — ounces, grams, sheets, count, or liters — the comparison is fair regardless of how the packages differ. The calculator computes both unit prices and names the cheaper option, or flags a tie when they match exactly. Grocery shoppers checking whether bulk really saves, anyone comparing brands and pack sizes, and bargain hunters wary of misleading 'value' labels use this to shop with confidence. Unit pricing is the single most reliable way to compare value at the shelf, and while many stores print it on the tag, the figures are often in tiny type or inconsistent units. Running the two numbers yourself guarantees an apples-to-apples answer every time.

Formula

Unit Price A = Price A ÷ Size A; Unit Price B = Price B ÷ Size B; Better Deal = whichever unit price is lower

Package prices are hard to compare because they bundle different quantities, so a bigger number on the shelf does not reliably mean a worse deal. Dividing each product's price by its size strips the packaging away and reduces both to the same common denominator — the cost of a single unit. Once both are expressed per unit, comparison becomes trivial: the lower figure is objectively cheaper per unit, and the calculator flags it, or reports a tie when the two unit prices are equal.

Source:Standard cost calculation

We review all our tools from time to time to ensure accuracy.

Worked example

Product A Price ($):6Product A Size (units):12Product B Price ($):4Product B Size (units):10

Product A costs $6.00 for 12 ounces, or $0.50 per ounce. Product B costs $4.00 for 10 ounces, or $0.40 per ounce. Even though B has a lower sticker price and less product, it is also cheaper per ounce, so B is the better deal.

How to use this calculator

1
Enter your values
Enter product a price ($), product a size (units), product b price ($) and product b size (units).
2
Adjust the options
Fine-tune any options to match your situation.
3
Read your result
Product A Unit Price updates instantly as you type — no button to press.

Frequently asked questions

What units should I enter for size?

Use any unit you like — ounces, grams, milliliters, liters, sheets, or item count — as long as you use the exact same unit for both products. The calculator compares them on equal footing, so mixing units, such as ounces for one and grams for the other, produces a meaningless result. If two packages list different units, convert one so both match before entering, then the per-unit comparison will be accurate.

Is the bigger package always cheaper per unit?

Not always. Buying in bulk usually lowers the unit price, but not reliably — retailers sometimes price larger 'value' or 'family' sizes higher per unit than the standard package, counting on shoppers to assume bigger means cheaper. Promotions, coupons, and store-brand versions can also flip the math. That uncertainty is exactly why checking the actual unit price matters; never assume the largest option wins without confirming the numbers.

Should I factor in whether I'll use it all?

Yes. A lower unit price only saves money if you actually use the product before it expires or goes stale. A giant jar that is cheaper per ounce becomes the worse deal if half of it is thrown away. For perishables and items you use slowly, weigh the unit-price savings against realistic consumption. For shelf-stable goods you reliably use, the cheaper unit price almost always wins.

Does this handle multi-buy or sale prices?

It handles them if you enter the effective price and total size. For a 'buy 2 for $5' deal, enter $5 as the price and the combined size of both items. For a percentage-off sale, enter the discounted price. The calculator always works from whatever price and size you give it, so translate any promotion into the real total you pay and the real quantity you receive before comparing.

Why compute unit price myself if the shelf tag shows it?

Store unit-price labels are helpful but inconsistent. Different products on the same shelf are sometimes priced per ounce, per 100 grams, or per count, which defeats direct comparison. Tags can be outdated, missing on sale items, or printed in hard-to-read type. Running the two numbers yourself guarantees both are measured the same way and reflect the current price, giving you a trustworthy answer instead of relying on labels that may not line up.