Choosing a small pet, starting from the housing

Almost every guide to choosing a small pet compares temperament: which is friendlier, which is easier to handle, which is more active in the evening. Those are real considerations and they are the wrong place to start, because temperament is a preference and housing is a constraint. A species you love that needs 64 square feet you do not have is not a good match, and no amount of enthusiasm changes the arithmetic.

So this section starts from the enclosure. For each species: the published floor-area minimum, what housing that actually costs to buy, how long the animal lives, and how much daily time it takes. Those four numbers eliminate most options for most households before temperament comes into it, which saves everyone — including the animal — a great deal of trouble.

The four species, on the numbers that constrain you

The striking thing in that table is that the space requirement and the lifespan run together. The species needing the least floor lives the shortest time; the species needing an eight-foot square is a commitment of up to a decade. Which means the honest first question is not which animal you like, but which combination of space and years your household can hold.

Where each species is genuinely a poor choice

We are going to be direct about this, because guides in this category tend not to be and the cost of that vagueness is animals rehomed at six months.

• Rabbits are a poor first small pet for most households, not because they are difficult animals but because 64.5 square feet in one unbroken block is a genuinely large commitment, and because they live up to twelve years. They are also, contrary to their reputation, not especially suited to being handled by children.
• Hamsters are a poor pet for a young child who wants to play with an animal in the daytime. They are nocturnal, they are solitary, and they sleep through exactly the hours a child is available. This is the single most common mismatch in this category.
• Ferrets are a poor pet for anyone who cannot give two to three hours a day of supervised out-of-cage time, which VCA publishes as a requirement rather than a nicety. They also need a ferret-proofed space, which is a bigger job than it sounds.
• Guinea pigs are a poor pet for anyone who wants one animal. They are obligately social, so the decision is always about a pair, which doubles the space requirement and the cost.

None of those is a reason nobody should keep these species. They are reasons to match the species to the household rather than the other way round, which is what best small pets and best small pets for beginners work through in detail.

Housing cost, which is most of the real cost

Prices on this site are read from the listing daily and shown inside the buy button rather than written into prose, for the reasons set out in how we assess products, so what follows is about relative cost rather than figures we typed. The pattern is consistent across species: the enclosure that clears a published minimum costs several times the enclosure sold on the shelf next to the animal, and it is the single largest purchase you will make.

The good news is that floor area is the cheapest specification to satisfy if you are willing to assemble rather than buy. A converted storage tub clears the hamster minimum for less than a pet-store starter cage. Four joined exercise pens clear the rabbit minimum for less per square foot than any hutch. A modular C&C cage clears the guinea pig preferred figure for less than a purpose-built habitat of smaller area. In every case the premium product is buying convenience and finish, not space.

Choosing by your constraint

If space is what limits you, best small pets for apartments works through what fits in a flat, honestly — which mostly means one species rather than four. If you are choosing for a child, best small pets for kids is explicit about the nocturnal problem and about who actually ends up doing the cleaning. And if someone else has just acquired the animal and you are buying for them, gifts for a new small-pet owner covers what genuinely helps rather than what fills a box.

One last framing, because it is what this whole site is for. The question is not whether you can house an animal at the published minimum. It is whether you can do that and then keep doing it for the species' whole life, including the years when the novelty has gone. The species whose minimum you can clear comfortably is a better match than the species whose minimum you can just about reach.

One species sits just outside the four above and is covered here rather than in a hub of its own. Rats need a taller, narrower-barred enclosure than any of them, and the cages that suit them are sold under other animals' names, so the best rat cages assesses five of those against the published figures. How big a rat cage should be sets out the three published positions and why they are so far apart, and rat cage bar spacing covers the half-inch rule that rules out the cheaper half of the category.

Gerbils sit here for the same reason, and they are the species where the published guidance is strictest about what you may not buy: the RSPCA advises against bar cages altogether. Best gerbil cages is the short list of enclosures that match what the charities actually describe, best gerbil bedding does the substrate arithmetic — a pair at the published depth needs 100 liters or more, which is larger than any pack on sale — and gerbil vs hamster compares the two burrowers on the figure that separates them, which is that the same 100 x 50cm floor houses one hamster or two gerbils.