Our methodology
How we analyze food for dogs and cats.
Our approach
PetFoodStats is a nutritional analysis tool for dog and cat food. No brand can pay to influence its score or ranking. If affiliate links to retail sites are present, they have no impact on analysis results.
Our goal is to provide a clear, factual framework to help pet owners compare the nutritional compositions of products available on the market.
The score we assign reflects an assessment of the composition declared by the manufacturer. It is not a value judgement on the brand, and does not replace veterinary advice.
Where does the data come from?
Nutritional data (protein, fat, fiber, ash, moisture, etc.) is collected from information published by manufacturers on their packaging, official websites, and technical sheets.
PetFoodStats does not perform laboratory analyses. We work exclusively from declared data. This means our scores reflect what the manufacturer communicates, not an independent measurement of the actual composition.
When a data point is not disclosed by the manufacturer (for example, kibble moisture or metabolizable energy), we apply a standardized estimate, clearly indicated on the product page.
How does the scoring work?
Each product is evaluated on a set of nutritional criteria grouped into three families:
Nutritional profile
Analysis of protein, fat, carbohydrate, fiber, ash, and mineral levels (calcium, phosphorus), as well as key ratios (calcium/phosphorus, omega-6/omega-3, protein/ash, fat/protein).
Ingredient quality
Assessment of animal protein content, presence of fresh meat, absence of high glycemic index ingredients, taurine status, and absence of controversial additives (BHA, BHT, ethoxyquin).
Transparency and manufacturing
Consideration of the declared cooking method (extrusion, low temperature, freeze-drying) and fat traceability (named or generic source).
The score is calculated for multiple profiles (adult, senior, puppy/kitten, neutered, active) because nutritional needs vary with age, size, and lifestyle. Reference thresholds are adjusted accordingly.
The total score (out of 100) is converted into a letter grade:
Label percentage vs scored value: an energy-based approach
Since September 2026, we no longer score nutrient percentages (protein, calcium, phosphorus, ash) as printed on the packaging. We first convert them to grams per 1000 kcal of metabolizable energy (g/Mcal), the scientific basis used by FEDIAF (Table III-4b), AAFCO and NRC.
Why the change?
A pet needs a fixed amount of energy per day, regardless of how calorie-dense its food is. Two kibbles showing the same calcium percentage can deliver very different real doses depending on their caloric density. The g/Mcal basis corrects this distortion by measuring what's actually ingested per day, not the label percentage.
A concrete example
Two kitten kibbles at 1.1% calcium. The denser one (400 kcal/100g) delivers 2.75 g calcium per 1000 kcal ingested. The less energy-dense one (340 kcal/100g) delivers 3.24. For a kitten with a fixed energy need, the second provides more calcium in absolute terms — and will score better on this criterion, despite an identical label percentage.
What you see on product pages: The displayed rate remains the raw percentage declared by the manufacturer (as printed on the package). Only the internal scoring uses the g/Mcal basis, not the display. This keeps the number consistent with what you can verify on the packaging.
Criteria concerned: Protein-to-Calorie Ratio (RPC), Calcium, Phosphorus and Ash — for both dry and wet food, dog and cat.
Reading a score properly
A score is not a universal rating. Three key principles to use it well:
Compare within a category, not between categories
Scoring thresholds differ by food type (kibble, wet, raw, home-cooked, freeze-dried, treats). Industrial process, digestibility, water content and physiological needs vary dramatically from one category to another. A B on kibble and a B on wet food do not mean the same thing and cannot be directly compared.
A lower score may suit your pet better
A product graded C or B can sometimes be more appropriate than one graded A, depending on your pet's profile: age, weight, activity, spay/neuter status, condition (renal insufficiency, digestive sensitivity, food allergy…). The score reflects a generic quality for a given physiological profile - but your vet knows criteria no algorithm can anticipate.
A score never replaces veterinary advice
PetFoodStats is a decision-support tool, not a diagnosis or prescription. In case of doubt, a diagnosed condition or a significant diet change, consult your vet - they are the only professional qualified to recommend a diet based on the complete health assessment of your pet.
What do we base our work on?
The thresholds and criteria used in our algorithm are informed by recommendations from leading animal nutrition organizations:
- FEDIAF (European Pet Food Industry Federation) - Nutritional Guidelines, current edition.
- NRC (National Research Council) - Nutrient Requirements of Dogs and Cats, the reference publication on nutritional needs.
- AAFCO (Association of American Feed Control Officials) - Dog and Cat Food Nutrient Profiles.
These organizations provide ranges that are sometimes broad, and do not cover every criterion we evaluate. When official recommendations do not allow for a precise threshold, we make an editorial judgement based on available literature and our experience. These choices are acknowledged and may evolve over time.
Official recommendations evolve with the state of knowledge. Our algorithm is regularly updated to reflect these changes and refine our own editorial choices.
Redhibitory alerts
Certain criteria can trigger a redhibitory alert, regardless of the overall score. These are situations where a nutritional value exceeds a threshold considered risky by reference organizations.
Examples: excessive calcium for a large-breed puppy, a very unbalanced calcium/phosphorus ratio, or the presence of additives classified as controversial.
These alerts are clearly displayed on the product page. They do not modify the score itself, but signal an important point of concern.
What our score does not measure
In full transparency, here is what our scoring system cannot evaluate:
- Actual nutrient digestibility - two foods with the same protein level can be absorbed very differently by the body.
- Mineral and vitamin bioavailability - the chemical form of a nutrient influences its absorption.
- Organoleptic quality - palatability, texture and taste matter to the animal but cannot be measured from a label.
- Individual needs - an animal with a medical condition (kidney, cardiac, allergy) may require a specific food that a general score cannot reflect.
- Actual raw material quality - the label states the category ("chicken"), but not the quality of the batch used.
- Storage conditions and product freshness at the time of purchase.
Our commitment
We are committed to maintaining our editorial independence. No manufacturer can pay to improve their products' scores.
If you notice an error in a product's data, please let us know. We correct confirmed errors as quickly as possible.
Our algorithm evolves. When new scientific data or official recommendations are published, we adjust our thresholds and criteria accordingly. A score may therefore change over time without the product's composition having changed.
Important notice
The information presented on PetFoodStats is provided for informational purposes only. It does not constitute veterinary or professional nutritional advice. For any medical condition or specific need, consult your veterinarian. The publisher disclaims all liability for dietary choices made based on this information.
Read the full disclaimer