Disclosure: PricePing makes this free tool. It runs entirely in your browser: nothing you type is sent anywhere or saved, and there is no sign-up.
How it works
The calculator turns every option into the same unit, then divides its price by the total amount: size × pack count. It shows each option’s price per kg or litre when you use metric sizes, per ounce, pound or fl oz when you use US sizes, and per item for counts. The cheapest option is marked, and every other one shows how much more it costs for the same amount.
- Mix units freely within a kind: grams with kilograms, ml with litres or fl oz.
- Leave “Pack of” empty for a single item.
- Up to six options at once.
When unit price matters most
Unit price is the fair way to compare sizes of the same product, the same product from two stores, or an offer on a small pack against the everyday price of a big one. It doesn’t account for waste: a big pack is only cheaper if you use it before it goes off.
Questions
How do I calculate unit price?
Divide the price by the amount. A 500 g pack at 4.99 is 4.99 ÷ 0.5 kg = 9.98 per kg; a 1 kg pack at 8.99 is 8.99 per kg, so the bigger pack is cheaper per kilo. Convert both packs to the same unit first; the calculator does that for you.
Is the bigger pack always cheaper?
No. Bigger packs are often cheaper per unit, but not always, especially when the smaller size is on offer. Comparing the unit price is the only way to know.
How do I compare a multipack?
Enter the size of one item and how many are in the pack. A 6-pack of 330 ml cans is 1,980 ml in total, and the calculator divides the price by that.
Can I compare grams with millilitres?
No. Turning a weight into a volume needs the product's density, which isn't on the label, so the calculator only compares weights with weights, volumes with volumes and counts with counts.
Are fluid ounces and gallons US or UK measures?
US: 1 fl oz is 29.57 ml and 1 gallon is 3.785 litres. Ounces (oz) and pounds (lb) are weights, the same in the US and the UK.
Which currency does it use?
Any. Type every price in the same currency; the calculator doesn't convert between currencies.
More free shopping tools
- Amazon link cleaner: Turn a long Amazon product link into the short /dp/ form and strip the tracking. Works for amazon.com, .co.uk, .ae, .sa and other Amazon stores.
- Discount calculator: Work out a sale price, stack an extra discount on top (30% + 20% is 44%, not 50%), add sales tax, or find the % off between two prices.
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