Compare daily calorie and food portion requirements between cat breeds. See how a Maine Coon's feeding needs differ from a Siamese or Munchkin based on AAFCO and WSAVA metabolic formulas.
A 5 lb Singapura and a 25 lb Maine Coon do not eat the same -- but even at the same weight, breeds differ in metabolism and frame. The Breed Size Feed Comparison Calculator compares calorie needs across breeds and sizes so you can portion realistically for your cat's build.
Owners of small or large breeds often mis-portion: small breeds get too much (easy keepers gain fast), large breeds get too little relative to their lean mass. Comparing breeds on a level basis prevents both errors.
Calorie need scales with lean body mass, estimated via the RER formula 70 x kg^0.75 -- note the 0.75 exponent means bigger cats need more total calories but fewer per pound than small cats. A 20 lb cat needs more than a 10 lb cat, but not twice as much; per-pound need falls as size rises.
Breed metabolism varies. Lean, active Oriental breeds (Siamese, Bengal, Abyssinian) run hot and may need more calories per pound than stocky, calm breeds (British Shorthair, Persian, Ragdoll) that trend toward obesity. Hairless breeds (Sphynx) burn extra staying warm and often need 1.2-1.5x a coated cat's calories at the same weight.
Frame matters more than the scale number. Two cats both weighing 12 lb can have very different ideal intakes if one is a muscular Bengal and the other a round British Shorthair. Body condition scoring -- not the number alone -- should confirm the portion.
Using the tool takes under a minute. Enter your cat's current weight in pounds (or kilograms, if your page allows), select the relevant life stage, health, or activity options, and press the calculate button. The result shows a daily calorie target plus dry, wet, and mixed-food portions you can measure.
Read the result as a starting point, not gospel. Weigh your cat every 2-4 weeks and nudge portions up or down by about 5-10% if the body condition drifts from ideal. Keep a simple log -- date, weight, cups/cans -- so trends are obvious before they become problems.
The most common error is eyeballing portions instead of measuring. A 'scoop' varies by 30-50% between people, and those calories accumulate into slow weight gain. Use a real measuring cup or kitchen scale, especially for dry food.
A second mistake is treating treats and table scraps as free. They can silently add 10-20% of daily calories; count them toward the budget or switch to tiny training treats. A third is free-feeding dry food without monitoring intake, which makes overfeeding effortless for easy-keeper cats.
Giant breeds mature slowly. Maine Coons and Norwegian Forest Cats keep growing (and needing growth food) to 18-24 months, so their intake stays high longer than a small breed's. Adjust expectations by breed, not just age.
Small breeds are easy keepers. Singapura, Devon Rex, and similar tiny cats gain quickly on standard portions; measure carefully and favor high-protein food to preserve lean mass. See the adult feeding calculator for the base target.
Your daily calorie number assumes a healthy, stable adult at a lean body condition. Kittens, pregnant or nursing cats, seniors, and overweight cats each get different factors -- that is why we offer a dedicated calculator for each. If your situation spans categories, start with the most specific tool and confirm with your veterinarian.
Adjust in small steps. A 5-10% portion change is enough to move weight gradually; dramatic cuts risk nutrient shortfalls or, in cats, hepatic lipidosis. Track weight monthly and let trends -- not a single weigh-in -- guide tweaks.
Worked example: compare a 12 lb Bengal and a 12 lb British Shorthair, both neutered adults. RER for 12 lb (5.4 kg) = 70 x 5.4^0.75 = about 240 kcal. The Bengal is a lean, high-metabolism breed and may need the upper end (about 1.3-1.4x = 310-340 kcal), while the British Shorthair is a calm, easy-keeper breed that trends toward obesity and may do better near 1.1-1.2x (about 265-290 kcal). Same weight, different targets -- because frame and metabolism differ. A 20 lb Maine Coon (9.1 kg) has RER about 350 kcal and, even at 1.2x, needs about 420 kcal -- more than the small breeds but fewer per pound. Confirm with body condition, not the scale alone. Remember that individual cats vary: a very active Bengal may need more than a couch-potato Bengal, and a Domestic Shorthair of the same weight may fall anywhere on the range. Use breed as a starting assumption, then adjust by body condition. If ribs are hard to feel or the waist disappears, feed for the lower end of the range; if the cat is too lean, feed toward the higher end. The calculator gives you a data-driven baseline, but the cat's body tells you the final answer.
A myth is that a bigger cat simply eats twice a smaller one; because need scales with weight to the 0.75 power, per-pound need falls as size rises. Another is that all small breeds are low-maintenance; tiny easy-keepers like the British Shorthair gain readily and need careful portions. And that breed alone sets the number -- body condition still confirms it, since two same-weight cats can have different frames.
Use the calculator for routine portioning, but let your vet lead on medical nutrition. Sudden weight loss or gain, increased thirst or urination, persistent vomiting, appetite swings, or a new diagnosis (kidney disease, diabetes, hyperthyroidism) all warrant a check-up before changing the diet. Therapeutic prescription diets should be started under veterinary guidance.
Select two breeds and enter weights to compare their daily calorie and food portion requirements.
Yes, significantly more. A typical 18-pound Maine Coon needs approximately 466 kcal/day (RER × 1.2), while a 6-pound Munchkin needs only 181 kcal/day. The large breed requires 2.6 times more calories daily, which translates to 0.81 more cups of dry food per day, or about 25 more pounds of dry food per year. Our calculator above shows the exact difference for your cats' specific weights.
No, AAFCO sets a single nutrient profile for "all life stages" that applies to all breeds equally. However, large breeds benefit from diets with joint-supporting supplements (glucosamine, chondroitin) and controlled calcium-phosphorus ratios, while small breeds with high metabolisms may need higher-calorie-density food. The feeding amount difference is driven by body weight and metabolic rate, not AAFCO standard differences. Use our basic adult calculator for single-breed calculations.
Using a mid-range $3.50/lb dry food (approximately $0.40 per 350-kcal cup), feeding an 18-pound Maine Coon costs about $0.53/day or $194/year. A 6-pound Munchkin costs about $0.21/day or $76/year. The annual feeding cost difference is approximately $118 per year per cat. For premium foods costing $5-7/lb, the gap widens to $200+ per year. The calculator above shows your exact cost difference based on your chosen food type.
While not strictly necessary, it is beneficial. Large breeds benefit from "large breed" or "joint health" formulas with glucosamine and controlled calorie density. Small breeds may prefer smaller kibble sizes and higher-calorie-density food to meet their needs in smaller portion volumes. Some manufacturers offer breed-size-specific formulas, but any AAFCO-compliant adult cat food works for both — the key difference is portion size, which our calculator determines precisely using WSAVA formulas.