Calculate daily food portions for rabbits, hamsters, guinea pigs and more. Get hay, pellet, and veggie amounts plus foods to avoid | Calculator4U
Calculate daily food requirements for rabbits, guinea pigs, and hamsters.
Provide a highly calibrated, scientifically backed diet for your pocket pet with the Small Mammal Nutrition Calculator. Small exotic pets—including rabbits, guinea pigs, chinchillas, hamsters, rats, gerbils, mice, hedgehogs, and sugar gliders—possess highly specialized digestive tracks that demand strict macro- and micronutrient distributions. Just as traditional pets rely on precise caloric targeting, small companion mammals require exact dietary volume scaling based on their metabolic body weight, species-specific digestive anatomy, and life-stage factors. This tool automates complex dry matter ratio balancing to ensure your pet receives optimal levels of crude fiber, life-sustaining vitamins, and essential proteins while safely limiting carbohydrate intake.
For hindgut fermenters like rabbits, guinea pigs, and chinchillas, the biological cornerstone of wellness is continuous access to premium, long-strand grass hay (such as Timothy, Orchard, or Meadow hay). This high-fiber ingestion drives essential cecal fermentation, fuels continuous gut motility, and provides the mechanical wear required to naturally grind down ever-growing hypsodont teeth. Without precise structural alignment, these animals are highly vulnerable to life-threatening gastrointestinal stasis (GI stasis) and dental malocclusion. Conversely, omnivorous rodents require a varied seed block and protein mix, while obligate carnivores like ferrets demand zero plant carbohydrates to protect against metabolic complications like insulinoma.
A major evolutionary gap addressed by this calculator is the unique mutation in guinea pigs, which lack the L-gulonolactone oxidase enzyme needed to synthesize endogenous Vitamin C. To completely ward off severe clinical scurvy, they depend entirely on a external intake of 10–30 mg of stabilized Vitamin C every single day from fortified pellets and fresh, low-oxalate vegetables.
| Species | Dietary Classification | Hay Requirement | Critical Physiological Notes |
|---|---|---|---|
| Rabbit | Herbivore / Lagomorph | 80%–85% of total diet | Requires high crude fiber to prevent GI stasis and tooth overgrowth. |
| Guinea Pig | Herbivore / Cavy Rodent | 80% of total diet | Must ingest 10–30 mg of daily Vitamin C to prevent scurvy. |
| Chinchilla | Arid-Adapted Herbivore | 80%+ of total diet | Extremely sensitive cecum; requires low-moisture foods to prevent bloat. |
| Ferret | Obligate Carnivore | Strictly 0% (Toxic) | High-carbohydrate or high-fiber foods promote pancreatic tumors. |
| Hamster & Gerbil | Omnivore | Bedding / Foraging only | Prone to diabetes; require strictly limited sugar and high-quality seed proteins. |
| Sugar Glider | Nectarivore / Omnivore | 0% (Not digestible) | Requires a strict 2:1 Calcium to Phosphorus ratio from sap and insect targets. |
For a standard 2.00 kg (4.4 lbs) Adult House Rabbit: The mathematical target outlines a recommended dry matter intake consisting of unlimited Timothy grass hay (roughly equal to their total body volume daily), paired with exactly 12 grams of high-fiber nuggets and 60 grams of diverse, low-calcium leafy greens (such as romaine lettuce, cilantro, and parsley). High-sugar fruits must be restricted to a maximum of 1–2 teaspoons per day.
| Animal Configuration | Metric Weight | Pellet Allocation | Fresh Botanical / Protein Feed |
|---|---|---|---|
| Dwarf Rabbit Breed | 1.00 kg (2.2 lbs) | 6.0 grams | 30.0 grams dark leafy greens |
| Commercial / Standard Rabbit | 2.00 kg (4.4 lbs) | 12.0 grams | 60.0 grams mixed leafy greens |
| Adult Guinea Pig (Average) | 0.90 kg (2.0 lbs) | 15.0 grams | 50.0 grams high-C bell peppers |
| Syrian Hamster (Adult) | 140 grams (0.3 lbs) | 1–2 tbsp seed mix | 1 thin slice of cucumber (treat only) |
Note: All species listed require unmetered access to loose grass hay except for omnivorous hamsters.
| Nutrient Profile | Rabbits / Chinchillas | Guinea Pigs | Ferrets |
|---|---|---|---|
| Crude Fiber (Minimum) | 18% – 25% | 15% – 22% | Below 1.5% (Trace amounts only) |
| Crude Protein (Optimal) | 12% – 14% | 14% – 16% | 35% – 40% Minimum |
| Crude Fat (Maximum) | 2% – 4% | 3% – 4% | 18% – 22% (Vital fuel source) |
| Vitamin C Strategy | Endogenous Synthesis | 10 – 30 mg Daily | Endogenous Synthesis |
An adult rabbit's diet should be roughly 80% unlimited grass hay, with about one packed cup of leafy greens and 1/8 to 1/4 cup of pellets per day for a 2 kg rabbit. Enter your rabbit's actual weight in the calculator above for a portion estimate tailored to their size.
Guinea pigs lack the enzyme needed to synthesize vitamin C, unlike rabbits, so it must come from their daily diet through fortified pellets and vitamin C rich vegetables like bell peppers. Without it, guinea pigs can develop scurvy within a few weeks.
Foods to avoid for rabbits include iceberg lettuce (no nutritional value), avocado, rhubarb, onion-family vegetables, seeds and nuts, cereal or grains, and excess fruit or root vegetables. These can cause digestive upset or, in the case of avocado and rhubarb, be seriously toxic.
Hamsters should have fresh food available daily, typically a seed and grain based mix supplemented with small portions of fresh vegetables. Because hamsters are prone to obesity, portion control matters more than feeding frequency.
The calculator estimates daily food needs from the animal's species and body weight, since different small mammals have different metabolic rates and diet compositions. Herbivores like rabbits and guinea pigs need hay-dominant diets, while omnivores like hamsters and rats need a more balanced pellet and protein mix.
Yes. Unlike most rabbit-only or hay-only calculators, this tool covers 11 species including omnivores like sugar gliders, insectivores like hedgehogs, and obligate carnivores like ferrets, each with its own diet class and feeding guidance.