Nutrition facts scanner: the whole label, explained

What the scanner returns

Scan a barcode and you get the full panel as the manufacturer declared it: energy in both kcal and kJ, protein, carbohydrate, of which sugars, fat, of which saturates, fibre, and sodium or salt. Where the database holds them, you also get Nutri-Score and the NOVA processing group.

Everything is shown for the portion you select rather than only per 100 g, because the per-100 g figure is a storage convention and not a thing anybody eats.

Reading each line

Energy: kcal and kJ

European labels lead with kilojoules; the number most people mean by "calories" is the kcal figure. One kcal is 4.184 kJ, so a 2,000 kcal day is about 8,400 kJ. We show both so a label from either regime is readable without arithmetic.

Protein

Four calories per gram. Usually the most useful single line on a label if you are trying to eat less overall: protein is the most satiating macronutrient per calorie, and the difference between a snack that ends hunger and one that does not is more often protein than calories.

Carbohydrate, of which sugars

Total carbohydrate includes starch and sugars together. The "of which sugars" line covers both added sugar and sugar naturally present, which is why plain milk and fruit show sugar values that look alarming and are not. The comparison worth making is between similar products: two breakfast cereals, not cereal against yoghurt.

A note on regional labelling: in the EU and UK, the carbohydrate figure already excludes fibre. In the US, total carbohydrate includes it, which is where "net carbs" as a concept comes from. The same food can therefore show different carbohydrate numbers in different markets without either label being wrong.

Fat, of which saturates

Nine calories per gram, more than double protein or carbohydrate, which is why fat content drives the calorie figure more than anything else. The saturates line is the one health guidance concerns itself with; most bodies suggest keeping it under about 10% of daily energy.

Fibre

Frequently the most informative line and the most ignored. Most people in Western countries eat around 15–20 g a day against recommendations of 25–30 g. When comparing two similar products, fibre is often the line that actually separates them.

Salt and sodium

Two ways of saying the same thing. Salt equals sodium multiplied by 2.5. UK and EU labels declare salt; US labels declare sodium in milligrams. Where a record carries only one, we convert and say so. The daily reference is about 6 g of salt, or 2.4 g of sodium, and processed food gets there faster than most people expect.

Nutri-Score and NOVA

Nutri-Score grades A to E from a single formula: energy, saturated fat, sugar and sodium count against, while protein, fibre and fruit-vegetable-nut content count for. It is a within-category tool. A cheese scoring D and a diet soft drink scoring B is not a statement that the soft drink is more nourishing — it means cheese is energy-dense, which you knew. Use it to choose between two breakfast cereals, not between a cereal and a yoghurt.

NOVA classifies by degree of processing, 1 for unprocessed through 4 for ultra-processed. It says nothing about calories or macros and is orthogonal to Nutri-Score: a food can be NOVA 4 and Nutri-Score A. It is a useful flag, not a verdict.

What labels are allowed to get wrong

Declared values are averages, not measurements of the packet in your hand. Both US and EU rules tolerate roughly 20% deviation for most nutrients, and permit rounding that compounds it — a US label may declare 0 g of fat for anything under 0.5 g per serving, which across several servings is not nothing.

This is worth internalising because it sets the ceiling on how precise tracking can be. A scanner reproducing a label exactly is still working with a figure that has a 20% tolerance built into it. Treating 187 calories as "about 190" is not sloppiness; it is reading the number correctly.

When the panel is missing

Some database records have a product name and no nutrition data. We show what exists and say the rest is missing, rather than filling gaps with a similar product's figures — a silent substitution is worse than an admitted gap, because you cannot correct what you do not know happened.

When that happens, type the panel in from the packet. It takes under a minute, and if you contribute it to Open Food Facts the next person to scan it gets a complete answer.

Scan a label now — your first one is free.