Is the big jar really the better deal? Type the price and the size and see what you pay per 100 g, per kilo, per ounce or per pound, whatever unit the label uses.
You pay
£2.50 for 500 g, which is 0.5 kg = 17.637 oz = 1.102 lb.
A unit price is the shelf price divided by how much is in the pack, scaled up to a round amount so that different pack sizes can be compared fairly. The calculator turns the pack into grams, millilitres or items first, then shows the price per 100 g, per kg, per ounce and per pound, or per 100 ml, litre, US fluid ounce and US gallon for liquids.
Unit price = price ÷ (packs × size of each) × the amount you want it per
Example: £2.50 for 500 g is 2.50 ÷ 500 = £0.005 a gram, so £0.50 per 100 g and £5.00 per kg. For a multipack, enter the number of packs and the size of one: 6 × 330 ml cans for £4.50 hold 1,980 ml, which is £2.27 per litre.
Many shops print a unit price, but not always in the same unit: one label says per 100 g, the next per kg, and imported goods may be priced per ounce or per pound. Putting everything into the same unit is the only fair comparison.
Every tool works in your browser, with metric and US units.
Line up several products in mixed units and rank them from best value to dearest.
Is the big pack still cheaper once you count what goes off before you finish it?
Cost per wear or per use, so a sturdier buy can be weighed against a cheaper one.
The old pack against the new one: how much more you really pay per gram or millilitre.
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Check a shop with WebTraceCheckEither, as long as both products use the same one. They are the same number with the decimal point moved, because a kilo is ten lots of 100 g. If one label shows £0.65 per 100 g and another £6.20 per kg, multiply the first by ten (£6.50 per kg) before you compare.
An ounce (oz) is a weight of about 28.35 g. A fluid ounce is a volume: about 29.57 ml in the US and 28.41 ml in the UK. Use ounces for solids such as cereal or coffee, and fluid ounces for drinks, sauces and shampoo.
Not directly. A litre of honey weighs much more than a litre of milk, so grams and millilitres only line up if you know the density, which labels rarely give. Compare products sold the same way.
Only the currency you pick, in your browser's local storage on this device, so the other tools use it too. Prices and sizes are never sent anywhere.