Methodology
How we score
Every Tallow score is a single number from 0 to 100. It is not a vibe and it is not a black box.
A product starts at 100 and earns specific, published penalties for what is actually in it and how it is made. The same math runs on every product, so two people who scan the same item always see the same score — and you can audit every line of it in the app on the “Why this score” breakdown.
The terms
How the number is built
Every product begins at a perfect 100. Penalties come off from there.
Every ingredient carries a severity rating from 0 (worst) to 4 (beneficial). The worst tier costs 40 points, the next 10, mild-caution ingredients 3, and neutral or beneficial ingredients cost nothing. Penalties stack — a mild ingredient can never dilute a terrible one.
Ingredients are listed by quantity, so a bad ingredient at the top of the list hurts more: the first ingredient's penalty is multiplied by 1.3, easing down to ×1.0 for the last.
The combined ingredient penalty is capped at 85 points. Two worst-tier ingredients near the top of the list hit the cap, and three always do — a genuinely harmful formula lands deep in Poor no matter what else is on the label.
A contaminant an independent lab actually measured is scored against its published limit rather than by severity rating. Under the limit it costs up to 20 points (half the limit costs 10); past it, every tenfold step costs another 30 — 10× the limit costs 50, 100× costs 80, and a reading roughly 460× over costs the full 100 on its own. The worst reading counts in full and every other one at half, capped at 100. A substance a lab looked for and did not detect costs nothing at all. A substance nobody has measured is not treated as absent — it keeps its ordinary ingredient penalty.
Industrial formulations built from additives, isolates, and ingredients you would not find in a home kitchen.
Processed culinary products — not whole foods, but not ultra-processed either.
Packaging is rated by material from 4 (best — glass, or no packaging at all) down to 0 (PVC, polystyrene, polycarbonate): the riskiest ordinary food-contact packaging costs 8 points, the best costs nothing. Two further tiers are set by hand for packaging that transfers into the food itself: 60 for a grinder whose mechanism is all plastic, grinding plastic into the salt, and 45 for a ceramic mechanism seated in a plastic head. Unknown packaging is never penalized.
Follows the USDA Organic certification, not the word on the front of the pack.
Grass-fed, pasture-raised, wild-caught and regenerative each add 3 points. These are the package's own words rather than an audited seal, so together they can add no more than 10. Organic and these claims are the only credits in the model; ingredients never buy points back.
A bioengineered (GMO) disclosure, or a label saying the food is lab-grown, 3D-printed or irradiated, costs 10 points each, capped at 20 together.
The total is rounded once and clamped to the 0–100 range.
Some products are shown as Unrated instead of getting a number: when there is no ingredient list, when half or more of what was read off the label is junk text rather than ingredients, or when ingredients on the list have not been rated yet. The one exception: if the rated ingredients already add up to 85 penalty points before position is counted, the product is scored anyway, because nothing still unrated could raise it. Never a misleading 100. No data is not the same as clean.
Ingredients
The ingredient severity ladder
Every ingredient in our database is rated 0 (worst) to 4 (beneficial). The penalty ladder is deliberately steep — a worst-tier ingredient costs four times a tier-1 and thirteen times a tier-2 — because one truly harmful ingredient should matter more than a pile of mild flags.
The worst offenders. One alone takes a product from 100 to somewhere between 48 and 60, and a few more flags push it into Poor.
Clearly harmful, but a notch below the worst tier.
Mild flags. A couple of these still leave a product Clean.
Neither good nor bad — costs nothing, buys nothing back.
Genuinely good ingredients. Highlighted, but they never add points — good stuff can't paper over bad stuff.
The output
Score bands
Poor
0–40
Okay
41–69
Clean
70–100
Processing
What is NOVA?
NOVA is a food-classification system from researchers at the University of São Paulo, widely used in nutrition science. It groups foods by how much industrial processing they have been through — which is why it carries weight in the score.
Tallow works the group out itself, from the ingredient list, following the marker list Open Food Facts publishes. Every ingredient gets a processing class, and the product takes the strongest signal on its label. One ultra-processed marker is enough for NOVA 4: any flavouring (including “natural flavors”), colours, emulsifiers, gums and thickeners, non-sugar sweeteners, flavour enhancers, and industrial ingredients like maltodextrin, glucose and corn syrups, hydrogenated oils, protein isolates, whey and modified starch. Vanilla, herb and spice extracts are not counted as flavourings. A product made only of culinary ingredients — salt, sugar, oil, butter, vinegar — is NOVA 2. Whole foods with salt, sugar, oil or a preservative added are NOVA 3, and plain whole foods are NOVA 1. Water, added vitamins, acids and cultures do not count either way.
NOVA does not apply to vitamins, minerals, herbal and other pill-type supplements, or to anything that is not food, so those have no group — protein powders and drink mixes are classified normally. If an ingredient on the list has not been classified yet and no ultra-processed marker has been found, the group shows as unknown and costs nothing, rather than being guessed.
- NOVA 1UnprocessedWhole foods — fresh fruit, eggs, plain milk, raw meat.
- NOVA 2Culinary ingredientsPressed, ground, or refined from NOVA 1 — olive oil, butter, salt.
- NOVA 3ProcessedNOVA 1 or 2 combined and preserved — canned beans, fresh bread, simple cheese.
- NOVA 4Ultra-processedIndustrial formulations with additives and isolates — soda, packaged snacks, most cereals.
Kid-Safe Mode
Kid-Safe Mode does exactly one thing: it subtracts a flat 5 points from any product that has never been lab tested at all. Every other term — ingredients, contaminants, processing, packaging, organic, label claims — is identical in both modes, so the Kid-Safe number is always just the ordinary score minus 5, or the ordinary score unchanged when a lab has tested the product.
It used to multiply every penalty by 1.5. That was removed: scaling the penalties while leaving the organic bonus flat quietly handicapped organic products, and the mode as a whole was hard to reason about. Feeding a child is the case where an unverified label deserves the least benefit of the doubt, so that is the only thing the toggle now expresses.
Restaurants
The restaurant map applies the same lens to places to eat — seed oils, additives, plastic contact, and premade food — but the scores are built from community ratings, weighted by the quality of each reviewer’s evidence. That model has its own page: how we score restaurants.
Personalization
Your standards
Alongside the number, Tallow can give a personal thumbs-up or thumbs-down against the standards you pick. It is one-strike: if any standard you selected fails, the product is rejected for you — regardless of its score. When the data needed for a check is missing, that check is marked unknown rather than quietly passed, and if every check is unknown you see “not enough info” instead of a fake approval. The standards you can pick:
- Artificial ingredientsAny ingredient in the two worst tiers (rated 0 or 1) — dyes, synthetic sweeteners, harsh preservatives — or a lab-measured contaminant at or above its limit.
- Ultra-processedThe product is NOVA group 4.
- Seed oilsCanola, soybean, corn, sunflower & co. — including the label names that hide them, like “vegetable oil”, shortening and margarine — or a lab finding that a cheaper oil was substituted for the one on the label. A certified seed-oil-free product passes outright.
- High sugarOver 22.5g per 100g (11.25g for drinks — the FSA “high” thresholds).
- High carbsOver 30g of carbohydrates per 100g.
- Risky packagingPackaging rated 1 or lower — most plastics (PVC, polystyrene, polycarbonate, generic and multilayer plastic), foil-lined wrappers, blister packs, poly-coated cups, and packaging that sheds into the food.
- GlutenAny ingredient that contains gluten — wheat, barley, rye, regular oats (oats sold as gluten-free pass) and the label names that hide them. A pass reads “no gluten ingredients listed”, never “gluten-free”: cross-contact is not on the label, so we will not promise it.
No black boxes. We do take money from brands and restaurants for placement and partnerships, and we say so when we do — but no payment has ever moved a score. The math on this page is the whole of it.