Free reference · Adult maintenance · NRC-sourced
How much should I feed my guinea pig?
Published guidance answers this with a formula, not a guess: an adult guinea pig needs about 136 × (body weight in kg)^0.75 kcal per day — the NRC maintenance value, which the source states for 400–600 g adults. A 1 kg (2.2 lb) adult guinea pig lands near 136 kcal a day. That number covers healthy adult maintenance only — nothing more.
Informational, not veterinary advice. What to actually put in the bowl — hay, pellets, fresh food, treats — is a different question this page does not answer; your vet should guide that.
Adult maintenance reference · NRC
The formula, and what it gives
136 × (body weight in kg)^0.75 kcal per day
| Adult weight | Maintenance kcal/day |
|---|---|
| 0.5 kg (1.1 lb) | ≈ 81 kcal |
| 0.8 kg (1.8 lb) | ≈ 115 kcal |
| 1 kg (2.2 lb) | ≈ 136 kcal |
| 1.2 kg (2.6 lb) | ≈ 156 kcal |
Source: NRC "Nutrient Requirements of Laboratory Animals": guinea pig maintenance ME ~= 136 x BW(kg)^0.75 kcal/day (stated for 400-600 g adults).
Checked against the source on 2026-08-08. The PetLife app computes this exact reference from the same constant, with the source named on screen.
Growing guinea pigs need more
The number above is for healthy adults. Growing, pregnant, nursing, and recovering guinea pigs need more than adult maintenance, and the cited guideline gives no factors for those stages — so neither does this page. If your guinea pig is young or in any of those situations, feeding amounts are a question for your vet, not a formula.
No weight-loss targets here — on purpose
The cited reference provides no weight-loss or weight-gain protocol for guinea pigs, so this page will not invent one. If your guinea pig is trending up or down on the scale, that is a vet conversation — not a formula.
What this page is — and is not
It is
An adult-maintenance energy reference from a named, published guideline — the formula, the citation, the date we checked it, and worked examples. It is the same constant the PetLife app uses for guinea pigs, so the page and the app cannot disagree.
It is not
A diet plan, a life-stage chart, or a weight-loss program. The cited references give no life-stage, spay/neuter, or weight-loss factors for guinea pigs — so this page refuses to invent them. The app takes the same position: it tracks what you feed and weigh, it never prescribes a treatment.
Keep the number where you feed
Track meals and weigh-ins against this reference, free, in the PetLife app
The iPhone app carries this exact guinea pig maintenance reference — with the source named on screen — and keeps meals and weigh-ins on one chart. One pet with core care logging stays free.
Why is there no bird page?
Because we could not find one honest number. The published avian energy literature is split on the key constant — a widely used non-passerine value (78) versus a psittacine-specific one (175), a 2.2× spread — and presenting either as the answer for your bird would be an invented choice. PetLife’s engine has a standing rule: no constant without a citation. Birds stay unsupported until the literature supports a number we can stand behind, and this page would rather tell you that than guess.
Have a dog or cat?
The interactive Feeding Calculator computes a personalized daily target for dogs and cats — life stage, spay/neuter, and body condition included. The calculator stays dog & cat only; guinea pigs and their neighbors get these sourced reference pages instead.
Informational, not veterinary advice.
This page is an educational reference built from the published guideline named above. Nothing here is veterinary or medical advice, a diagnosis, or a treatment plan. Always consult a licensed veterinarian about your guinea pig’s weight, diet, or health — and never delay or disregard professional veterinary advice because of something you read here. A pet that stops eating or loses weight quickly is a same-day vet call, not a reference-page question.