How the Grain Score is calculated.

Food and drinks: two parts, one number.

What a score is measured against. Solid foods are scored per 100 g. Grain divides the label's nutrition values by the serving's weight: the declared weight, or a declared volume or kitchen measure (like "½ cup") converted with a known density for that food. When a solid's label gives only a count, like "1 bar" or "3 cookies", Grain uses a typical portion for that kind of food, based on the FDA's reference amounts, and marks the score as based on an estimated serving. If it can't tell what kind of food it is, the product is "Not rated" rather than given a made-up serving. That way a small serving size can't make a product look better than what's in it. One exception, for now: when a label declares a serving under 1 g, like a pinch of spice, that serving's nutrition is scored as printed. Drinks are scored per serving, because that's what you drink, on a stricter sugar scale with a cap on sugar per 100 ml; a drink powder you mix yourself is scored per 100 g like a solid. When a drink's label gives no usable serving, Grain uses the FDA's reference amount for that kind of drink and marks the score as based on an estimated serving.

score = nutrition × 0.60 + ingredients × 0.40
        (a simple whole food with no nutrition label: 0.10 / 0.90)
then    floors: simple whole foods never below 78,
                clean-ingredient products never below 55
then    caps: drinks with no ingredient list (section 4);
        alcohol and tobacco are not rated

The nutrition side.

Solid foods. Per 100 g, energy, sugar, saturated fat and sodium each earn 0 to 10 points against the product, on the thresholds of the original Nutri-Score, before its 2023 update (sugar, for example, earns a point for every 4.5 g, up to 10 points at 45 g). Fiber and protein each earn 0 to 5 points for it. That gives 80 minus twice the difference. Protein doesn't count when the negatives are already high, unless the product is high in fiber or is a lean, high-protein food.

Three deductions can lower it further. When added sugar supplies 22%, 30% or 45% of the calories, 10, 22 or 40 points come off; for solid foods this applies only at 240 kcal per 100 g or more, and not to a sweetener sold on its own. For a product that also contains a hazardous or moderate additive, saturated fat of at least 3 g supplying 20% or 35% of the calories costs 15 or 25, and sodium of at least 300 mg at 2 mg or more per kcal costs 10. The nutrition score never goes below 0.

Added sugar counts in full. When a label declares added sugar, the rest of the sugar (the sugar that's naturally in fruit or milk) counts at 30%. Salty condiments used in small amounts, like soy sauce, miso or bouillon, are judged on the sodium in a real serving against the daily value, not per 100 g.

Drinks. A drink's nutrition score starts from its sugar per serving: water and unsweetened drinks with 10 kcal or less score 92, up to 5 g of sugar 78, up to 12 g 55, up to 20 g 30, and above that 8. More than 150 kcal a serving costs another 8 points, and more than 90 kcal with 12 g of sugar or less costs 5. When the label declares added sugar and a serving has at least 50 kcal, a further 10, 22 or 40 points come off as added sugar reaches 22%, 30% or 45% of the calories, so a full-sugar soda that declares its added sugar scores 0 on this side. When Grain knows the serving's volume, either the ml or fl oz on the label or the FDA reference amount it falls back on, a drink with 8 g of sugar or more per 100 ml can't score above 8 on this side, whatever the serving size, and one with 4.5 g or more can't score above 55. A serving given only as a count, like "1 can", or in grams has no volume to check, so this cap doesn't apply to it. A drink with almost nothing in it (5 kcal or less and 1 g of sugar or less per 100 ml, with almost no protein, saturated fat or fiber) gets a nutrition score of 25 instead of the sugar-based score if its ingredients include aspartame, sucralose, acesulfame, saccharin, cyclamate or neotame, E-numbers included. A sweetened drink that also has sugar, protein or calories is scored on the sugar scale above.

The ingredient side.

Every ingredient is matched against Grain's tiers. E-numbers and ingredient names in German, French, Spanish and Italian are translated first, so a label that says "E621" scores the same as one that says "monosodium glutamate".

Vague labels. A label that says only "flavouring", with no detail, caps the ingredient side at 66; one that says only "colour" caps it at 35, or at 68 on US and Canadian products, where that general word is the form the law requires.

The AI cross-check. Grain's AI explains every ingredient on a label. When it rates an ingredient that the tiers above don't cover as one to avoid, the ingredient side is capped at 49, and 7 lower for each further one, down to 20. When it rates one as caution, the cap is 100 minus 12 for each, down to 45. Ingredients the tiers already charge are never counted twice this way.

Some common ingredients are deliberately not treated as ingredients of concern, such as citric acid, xanthan gum, soy lecithin and natural flavors, because the evidence doesn't support it. Several of them still count toward the processing charge above.

Floors, caps and "Not rated".

Earlier versions of Grain capped scores by added sugar, sodium and saturated fat per serving. Scoring solid foods per 100 g made those caps unnecessary, and they were removed.

A worked example.

Your settings sit on top.

The score is a fact about the product. It's the same for everyone, and it's the number every screen shows. Your allergies, the ingredients you avoid and the certifications you prefer are applied on your phone, on top of it. If they move the number, the app shows the change next to the score, labelled as yours, and the breakdown says which setting moved it.

If a product contains an allergen in your profile, Grain doesn't adjust anything: it flags the product. People you add to your household are checked the same way, on your phone, and never change the score. Your health profile is never used to calculate the score itself.

Beyond food: the other four engines.

Beauty, feminine care and household products start at 100 and lose points for the ingredients of concern Grain recognizes; once anything is flagged, the score also weighs the beneficial ingredients it recognizes, so those can earn some points back. Supplements are built up instead, from formulation, purity and third-party testing, so a label with nothing flagged can still land below 100. Either way, these scores mostly describe what Grain recognized on the label, not how good a product is. 85 and up reads "No flags" only when Grain found nothing to flag; if it found a caution or avoid ingredient, or a supplement dose above an established upper limit, a score of 85 or more reads "Minor flags" instead. Below 85 the wording is "Minor flags", "Some flags", "Many flags" and "Serious flags" at the same 70, 50 and 30 steps as food. Each of these scores carries the note "Recognized ingredients only, not a safety or effectiveness rating".

Grain's stances.

Most tiers follow regulators and published evidence. A few rules are Grain's own judgement calls. The app labels them as stances, and so does this page:

• Synthetic dyes and artificial flavors are in the hazardous tier. That's a precautionary clean-label position with regulatory momentum behind it (EU child-attention warning labels, dyes under FDA review), not a claim of proven toxicity.
• Refined seed oils are shown but not scored. They used to be penalized. The evidence doesn't support that, so the penalty was removed; Grain still shows them so you can avoid them if you choose.
• Palm oil is charged for its saturated fat, not as a category.
• Loose talc and douches carry precautionary caps. They're framed as precautions, never as proven harm.

Sources and checks.

What changed, and what we don't know.

Changes since the July 2026 version of this page: solid foods are scored per 100 g instead of per serving; the per-serving sugar, sodium and saturated-fat caps were removed; the separate processing deduction became the processing charge on the ingredient side; refined seed oils are no longer penalized, and palm oil is no longer charged when the label shows the product is low in saturated fat (1.5 g or less per 100 g); 100% juice now has a floor instead of a cap; foods without a usable nutrition label, and beauty, feminine care, household and supplement products with no ingredient list, show "Not rated" instead of a provisional score; beauty products that list only "fragrance" or "parfum", without naming the allergens in it, lose 6 points; and non-food scores use the "No flags" to "Serious flags" wording.

Nutrition science isn't settled, regulators disagree, and brands change recipes without notice. The Grain Score is an estimate built from public data and published rules, with AI filling gaps, and it will sometimes be wrong. When an ingredient is genuinely contested, the app says it's a stance, not settled science.

Not medical advice. Always read the label, and talk to a qualified professional about health decisions.