How much food should a guinea pig have a day
A guinea pig should have about 152 g (5.3 oz) of food a day: unlimited hay, which comes to about 47 g (1.7 oz) for a 0.9 kg (2 lb) adult (Vethope veterinary clinic (Prague), Nutrition of guinea pigs (19 May 2025), 2026-09-19), a small measured 6.3 g (0.2 oz) of pellets (Vethope veterinary clinic (Prague), Nutrition of guinea pigs (19 May 2025), 2026-09-19) and about a cup, 98 g (3.5 oz), of fresh vegetables (PDSA, Your guinea pigs' diet (Oct 2024), 2026-09-19). Most of the weight is vegetables and most of the eating is hay. The chart below gives each line with its source, the second table scales hay and pellets to body weight, and the third turns it into bags per month for 1 to 4 guinea pigs.
Open the guinea pig food calculator
Guinea pig feeding chart: per animal per day
For one adult of 0.9 kg (2 lb) (Merck Veterinary Manual, table Physiological Data for Guinea Pigs (undated), 2026-09-19). These are the calculator’s starting values, each with its source and the date it was read; the calculator lets you change them.
| Food | Per day (g) | Per day (oz) | Source |
|---|---|---|---|
| Hay (unlimited) | 47 g | 1.7 oz | Vethope veterinary clinic (Prague), Nutrition of guinea pigs (19 May 2025), 2026-09-19 |
| Pellets | 6.3 g | 0.2 oz | Vethope veterinary clinic (Prague), Nutrition of guinea pigs (19 May 2025), 2026-09-19 |
| Fresh vegetables | 98 g | 3.5 oz | PDSA, Your guinea pigs' diet (Oct 2024), 2026-09-19 |
Vitamin C: guinea pigs cannot make it and need about 30 mg a day (Feeding (updated 14 Aug 2026), 2026-09-19), which is why the vegetables and the guinea pig pellets are not optional; the calculator shows the figure as information and does not compute it.
How much food should a guinea pig have by weight
Hay and pellets scale with body weight, at 52.5 g per kg of hay and 7 g per kg of pellets (Vethope veterinary clinic (Prague), Nutrition of guinea pigs (19 May 2025), 2026-09-19); the cup of vegetables is the same for every adult. Adult sows weigh about 0.7 kg-0.9 kg, boars 0.9 kg-1.2 kg (Merck Veterinary Manual, table Physiological Data for Guinea Pigs (undated), 2026-09-19).
| Guinea pig | Hay | Pellets | Vegetables | Total |
|---|---|---|---|---|
| 0.7 kg (1.5 lb) | 37 g (1.3 oz) | 4.9 g (0.2 oz) | 98 g (3.5 oz) | 140 g (4.9 oz) |
| 0.8 kg (1.8 lb) | 42 g (1.5 oz) | 5.6 g (0.2 oz) | 98 g (3.5 oz) | 146 g (5.1 oz) |
| 0.9 kg (2 lb) | 47 g (1.7 oz) | 6.3 g (0.2 oz) | 98 g (3.5 oz) | 152 g (5.3 oz) |
| 1 kg (2.2 lb) | 53 g (1.9 oz) | 7 g (0.2 oz) | 98 g (3.5 oz) | 158 g (5.6 oz) |
| 1.1 kg (2.4 lb) | 58 g (2.0 oz) | 7.7 g (0.3 oz) | 98 g (3.5 oz) | 163 g (5.8 oz) |
| 1.2 kg (2.6 lb) | 63 g (2.2 oz) | 8.4 g (0.3 oz) | 98 g (3.5 oz) | 169 g (6.0 oz) |
Hay, pellets and vegetables per month, and bags, for 1 to 4 guinea pigs
Adults at the calculator’s starting values. Per month is 30.44 days; bags are exact first, then rounded up to what you buy; “one bag lasts” is the bag weight divided by what the group gets through in a day.
| Guinea pigs | Hay per month | Hay bags (2.5 lb) | One hay bag lasts | Pellets per month | Pellet bags (5 lb) | One pellet bag lasts | Vegetables per month |
|---|---|---|---|---|---|---|---|
| 1 | 3.2 lb | 1.3 (buy 2) | 24 days | 0.4 lb | 0.1 (buy 1) | 360 days | 6.6 lb |
| 2 | 6.3 lb | 2.5 (buy 3) | 12 days | 0.8 lb | 0.2 (buy 1) | 180 days | 13.2 lb |
| 3 | 9.5 lb | 3.8 (buy 4) | 8 days | 1.3 lb | 0.3 (buy 1) | 120 days | 19.7 lb |
| 4 | 12.7 lb | 5.1 (buy 6) | 6 days | 1.7 lb | 0.3 (buy 1) | 90 days | 26.3 lb |
The same animals in kg, UK bags
| Guinea pigs | Hay per month | Hay bags (1 kg) | One hay bag lasts | Pellets per month | Pellet bags (3 kg) | One pellet bag lasts | Vegetables per month |
|---|---|---|---|---|---|---|---|
| 1 | 1.4 kg | 1.4 (buy 2) | 21 days | 0.2 kg | 0.1 (buy 1) | 476 days | 3 kg |
| 2 | 2.9 kg | 2.9 (buy 3) | 11 days | 0.4 kg | 0.1 (buy 1) | 238 days | 6 kg |
| 3 | 4.3 kg | 4.3 (buy 5) | 7 days | 0.6 kg | 0.2 (buy 1) | 159 days | 8.9 kg |
| 4 | 5.8 kg | 5.8 (buy 6) | 5 days | 0.8 kg | 0.3 (buy 1) | 119 days | 11.9 kg |
How much does guinea pig food cost?
No neutral source publishes a price for a bag of hay or of guinea pig pellets, and vegetable prices swing by shop and season, so this page carries no prices. The cost is the bag counts above times what you pay per bag, plus the vegetables per month times your price per weight; the calculator does the sum once you type your prices and says which lines still have none.
Why your guinea pig may eat more, or less
- Weight and sex: boars are heavier than sows and eat more hay and pellets; the cup of vegetables stays the same.
- Age and pregnancy: young, pregnant and nursing animals eat more and need more vitamin C; a vet sets the amounts.
- Waste: hay pulled out of the rack and soiled is not eaten; a rack that holds hay off the floor cuts the bag count.
- Pellets in a full bowl: a guinea pig that fills up on pellets eats less hay, so measure them rather than top up.
Work it out for your own guinea pigs
The guinea pig food calculator takes your animals, what each gets per day and the bags you buy, and gives hay, pellets and vegetables per day and per month, bags per month, how long a bag lasts and the cost from your own prices, in g and kg or oz and lb. Rabbits eat differently (more hay by weight, pellets by body weight, leafy greens rather than a mixed cup): see how many grams of food a rabbit eats per day or the rabbit food calculator.
Amounts are published averages for planning, not veterinary advice; a vet decides what an individual animal needs, and any sudden change in eating is a reason to see one.
Frequently asked questions
- How much should a guinea pig eat a day?
- About 152 g (5.3 oz) in total for a 0.9 kg (2 lb) adult: 47 g (1.7 oz) of hay, 6.3 g (0.2 oz) of pellets and 98 g (3.5 oz) of vegetables, with 30 mg of vitamin C a day from the vegetables and the pellets (Feeding (updated 14 Aug 2026), 2026-09-19). Hay is unlimited; the gram figure is what one animal gets through, for the shopping list.
- How much hay should a guinea pig have a day?
- As much as it wants: hay is 70-80 % of what a guinea pig eats and keeps the teeth and gut working. For buying it, count about 52.5 g per kg of guinea pig, 47 g (1.7 oz) a day for a 0.9 kg (2 lb) adult (Vethope veterinary clinic (Prague), Nutrition of guinea pigs (19 May 2025), 2026-09-19). Never let the hay rack run empty.
- How many pellets should a guinea pig have a day?
- About 6.3 g (0.2 oz) a day for a 0.9 kg (2 lb) adult, roughly a tablespoon (Vethope veterinary clinic (Prague), Nutrition of guinea pigs (19 May 2025), 2026-09-19), and only pellets made for guinea pigs, which carry vitamin C. Pellets are the smallest line by weight; a bowl kept full leads to an overweight animal that eats less hay.
- How many vegetables should a guinea pig have a day?
- About one cup, 98 g (3.5 oz), of mixed fresh vegetables a day (PDSA, Your guinea pigs' diet (Oct 2024), 2026-09-19): leafy greens and bell pepper most days, with small amounts of other vegetables, and fruit only as a treat. A cup of shredded leaves weighs far less than a cup of chopped pepper, which is why the gram figure is a midpoint.
- How many bags of hay do two guinea pigs go through a month?
- 6.3 lb (2.9 kg) a month for two 0.9 kg (2 lb) adults: 2.5 (buy 3) bags of 2.5 lb, one lasting 12 days, or 2.9 (buy 3) bags of 1 kg, one lasting 11 days. Wasteful eaters and soiled hay push it up.
- How much does guinea pig food cost a month?
- Bags per month x the price of a bag, plus vegetables by weight. For two adults that is 2.5 (buy 3) bags of hay (2.5 lb), 0.2 (buy 1) bags of pellets (5 lb) and 13.2 lb of vegetables a month; type the prices you pay in the calculator and the monthly cost appears. Hay is the bulk of the bill in weight, vegetables often in money.
More guides
- How much hay does a horse eat a day, a month and a year
Hay per horse per day from body weight, what to put out with waste, bales per week, month, winter and year, by weight, forage share and feeder, with sources.
- How many grams of food does a rabbit eat per day
Grams of hay, pellets and leafy greens per day for rabbits of 1 to 5 kg, adult and young, plus hay and pellets per month and bags for 1 to 4 rabbits, with sources.
- How much to feed chickens per day
Complete feed per hen per day by stage, and feed per day, per month, bags and cost for flocks of 3 to 50 birds, from published figures with their sources.
Last updated 2026-09-21. Figures are planning estimates built from published feeding guidance, each with its source and year: adjust for your own animals and follow the guide on the bag. Not veterinary advice.