FAQ: Wheels for small pets

The wheel should let the animal run with a straight back rather than one arched upwards. Hamsters and gerbils need a bigger wheel than is often assumed, so if in doubt, choose the larger diameter.

Legs, toes or tails can get caught between bars or rungs, which can cause dislocations and fractures. A solid running surface without gaps is much safer for all small pets.

An adult Syrian hamster is usually recommended a wheel of at least 28–30 cm in diameter, and larger individuals need an even bigger one. In a smaller wheel the animal runs with an arched back, which can harm the spine over time.

Djungarian, Campbell’s and other dwarf hamsters are usually fine with a wheel of 20–25 cm in diameter. The key is that the hamster does not arch its back while running, so a slightly bigger wheel is a better choice than one that is too small.

Although Roborovski hamsters are the smallest, they run a great deal, so a light, easy-turning wheel of at least 20 cm in diameter suits them. A wheel that is too stiff to turn can be awkward for such a tiny animal.

Gerbils are usually recommended a wheel of at least 25–30 cm in diameter with a solid surface. Because of their long tails it is especially important that the wheel has no cross supports or gaps where the tail could get caught.

Mice are usually fine with a wheel of 17–20 cm in diameter, but larger mice are better off with a bigger one. The wheel should be solid with no gaps near the axle, because mice’s tails and legs get caught easily.

Not all rats use a wheel, and those that do need one at least 30–35 cm in diameter so the back stays straight. Daily free-roaming time in a safe area, climbing and social contact matter far more to rats.

Degus are very active, so they are usually recommended a sturdy wheel of at least 30 cm in diameter with a solid surface. Because degus chew everything, a metal wheel works better than a thin plastic one.

Chinchillas are usually recommended a wheel of at least 38–40 cm in diameter, made specifically for chinchillas or animals of similar size. It should be sturdy, with a solid surface and no plastic parts the chinchilla could chew off.

No. The spine and body shape of guinea pigs and rabbits are not suited to running in a wheel, so a wheel can cause injuries. They need a spacious pen or a safe room where they can run freely.

Watch the hamster from the side while it runs: if its back is arched upwards and its head tilted up, the wheel is too small. In a suitable wheel the back stays straight or nearly straight.

It is usually worth buying a wheel sized for the adult animal straight away, because young ones grow quickly. A young hamster can use a bigger wheel as long as it turns easily.

A plastic wheel is lighter, quieter and often has a solid surface, but it can be chewed. A metal wheel is sturdier and chew-resistant, but it should have a solid rather than a barred running surface.

Wooden wheels are natural and many owners like them, but wood absorbs urine and odours, so they are harder to clean properly. Choose a wheel with a treated surface that is safe for small pets and keep it dry.

Barred and mesh wheels are not recommended, because legs and toes can get caught between the bars, and constant running on thin bars can cause foot inflammation. If you already have such a wheel, it is worth replacing it with a solid one.

A running saucer is a tilted spinning platform that the animal runs on. It does not suit every animal: the animal often bends its back sideways while running, so it is considered an extra activity rather than a replacement for a proper wheel.

A free-standing wheel is easier to move and suits tank-style enclosures and terrariums, while one mounted on the bars takes up less floor space and wobbles less. In both cases the wheel must stand level and not sway.

Wheels whose axle or support runs across the whole width create a so-called scissor effect: a tail or leg can get trapped between the spinning wheel and the fixed support. Wheels attached on one side only are safer.

The running surface should be wide enough for the animal to fit comfortably without its sides touching the edges. Larger animals, such as Syrian hamsters or degus, need wider wheels than mice.