Guinea Pig Care Calculator (Hay, Pellets, Veg, Vitamin C & Cage Size)

How it works

hay eaten ≈ 8% of body weight/day; offer 1.5× (wastage) · pellets ≈ 20 g (⅛ cup) adults, 30 g young · veg ≈ 100 g (1 cup) · vitamin C 10–30 mg/day · water ≈ 100 mL per kg · cage: 7.5 sq ft for 1–2 (recommended 10.5 for 2), +3 sq ft per extra pig; C&C grid = 14″ square

A guinea pig is a grazing animal whose teeth grow continuously and whose gut needs constant fibre, so the diet is mostly grass hay offered without limit, with a small measured ration of plain pellets and a cup of vegetables that must supply the vitamin C the species cannot synthesise — the nutritional fact that sets guinea pigs apart from rabbits and most other pets. Cage size is the other place where common practice falls short of need: the floor area recommended for a pair is several times what typical shop cages provide, which is why keepers build them from wire grids and coroplast. Quantities scale with body weight and herd size into a monthly shopping list dominated by hay.

Worked example

Two adult 1 kg guinea pigs each eat about 80 g of hay a day (offer 120 g — they nest in the rest), 20 g of pellets and 100 g of vegetables giving 15 mg of vitamin C, plus 100 mL of water; the pair needs about 7.2 kg of hay, 1.2 kg of pellets and 6 kg of vegetables a month — around $139 a month with roughly 234 L of bedding. Their cage should be at least 7.5 sq ft and ideally 10.5: a 2 × 4 C&C grid cage (2.3 × 4.7 ft).

Frequently asked questions