Every food gets a score out of 100, worked out the same way for every product. The numbers come straight from the label — we don't guess, and no brand can pay for a better score. Here's exactly what goes into it.
One honest caveat: labels differ. US-style labels state guaranteed analysis (minimums and maximums), EU-style labels state typical analysis (measured values). We use each label's numbers exactly as printed — so scores built on guaranteed values are close approximations, not lab measurements. Most labels also don't print carbohydrates at all: we calculate them as what remains after protein, fat, fiber, moisture and ash (and say so wherever the number appears). EU labels also list fewer additives (only those with a legal maximum must be declared) and may omit water used only in processing — so an EU ingredient list can be shorter than what the product actually contains. Every product page says which kind of label it uses.
Cats are obligate carnivores — they're built to eat meat. The score rewards foods that match that, and the three parts below add up to 100.
The 0–100 score maps to a letter grade so it's easy to read at a glance:
Because we measure one specific thing: how closely the label's ingredients and nutrient profile match what an obligate carnivore evolved to eat. Veterinarians weigh different things — feeding trials, manufacturing quality control, formulation research, and whether a diet manages a specific medical condition — and those factors are real, they just aren't on the label, so our score can't see them. A grain-heavy food from a research-driven brand can score low here and still be a diet your vet has good reasons to recommend, especially a therapeutic one (we tag those VET DIET and say clearly that the decision belongs to your vet). The two views answer different questions — ours is "what's in the bowl, by the label"; your vet's is "what does this particular cat need". When they disagree about your cat, your vet wins.