Methodology

PetMathStudiopublishes calculator-driven research. Every formula, coefficient, and threshold is sourced from a primary reference; we don't fabricate hobbyist anecdotes, and we don't lean on training-data fragments to fill in numbers. This page documents where the math comes from and how we verify it.

Sourcing tiers

Tier 1 — authoritative. National Research Council Nutrient Requirements of Dogs and Cats (NRC, 2006). WSAVA Global Nutrition Guidelines and the 9-point body condition score. AAFCO 2024 Nutrient Profiles. AAHA Senior Care Guidelines. AVMA dog-age and dog-life-stage statements. Every formula or constant tagged Tier 1 cites the original publication.

Tier 2 — industry technical references.Pet Nutrition Alliance calorie methodology. Purina Institute / Royal Canin Veterinary / Hill's professional product data sheets. Vetcalculators.com formula references. These are vendor or association resources — useful for cross-checking and for the kcal density of specific commercial diets.

Tier 3 — framed as such.ASPCA and AVMA pet-cost surveys. AKC breed-size and breed-weight reference tables. Banfield Pet Hospital reports. Used when nothing higher-tier exists; always named on the page that uses the number, not aggregated as “research shows.”

Rejected.Other pet-calculator sites (animal-calculator, dogscalculators, omnicalc and similar). Reddit threads, Amazon reviews, Pinterest, TikTok. Pet-blog content with no source attribution. If we can't trace a number to a Tier 1–3 source, it doesn't go on the page.

Worked example — dog calorie calculator

The dog calorie calculator estimates daily kcal need (Maintenance Energy Requirement, MER) from a Resting Energy Requirement baseline (RER) multiplied by a life-stage / neuter / activity factor.

Input: 22 kg adult neutered dog, body-condition score 5/9 (ideal), moderate daily activity.

Step 1 — RER. RER = 70 × kg^0.75 (NRC 2006, Ch. 3). At 22 kg: 22^0.75 ≈ 10.16, so RER ≈ 70 × 10.16 ≈ 711 kcal/day.

Step 2 — multiplier.Adult, neutered, moderate activity: 1.6× per the WSAVA / NRC consensus multiplier ladder (intact adult would be 1.8×; senior 1.2–1.4×; puppy under 4 months is 3.0× of RER). Multiplier source is named where it's applied.

Step 3 — MER. MER = RER × multiplier ≈ 711 × 1.6 ≈ 1,138 kcal/day. Round to 1,140 for display.

What this number is not: a personalized prescription. Real maintenance varies ±20% with breed, climate, metabolic individuality, and seasonal activity changes. The calculator surfaces the band, not just the midpoint, and the page says so. For weight-loss programs, prescription diets, or age-related illness, talk to a licensed veterinarian.

What we don't do

We don't fabricate personal stories. We don't cite publication numbers we haven't verified. We don't present AI-generated images as photographs. When a calculation has a known uncertainty, we state it conservatively rather than rounding optimistically.

Questions or corrections? Contact us.