Do Tarantulas Need a Lot of Space?
Keeping tarantulas is unlike the husbandry for many other exotic pets. It’s very common to come across a well-intentioned person new to the hobby who has previous exotics experience that expresses misplaced anger or disbelief at the way keepers set up their spider habitats.
While you certainly can provide a tarantula with an oversized cage, they do not require large amounts of space. Tarantulas are sedentary creatures that rarely leave their burrow even in the wild, only venturing out a short distance usually to look for food if it doesn’t come to them first. It is not cruel to keep tarantulas in small enclosures. As adults, the majority of species available to hobbyists can comfortably be kept in two-gallon and five-gallon tanks.
Is it okay to keep tarantulas in deli cups?
Slings can easily be kept in a deli cup or a small condiment container for the initial part of their lives provided that the cup is an appropriate size for the spider.
Both condiment cups and deli containers have been a hobby staple for years. Small Amac boxes that are 4-inches and under also work super well if you’re looking for a crystal-clear alternative to deli cups.
Adult tarantulas cannot be kept deli cups; however, I haven’t come across any hobbyists who thought they could do this.
I have come across people who mistakenly thought vendors were keeping adults in deli cups when in reality the tarantulas were just in temporary containers for a show or transportation to a new enclosure.
Do tarantulas need extra room in the cage to play or exercise?
Tarantulas do not need or want a lot of space. There is no need to give them extra room in an enclosure to play or to exercise, however, people often do because they hold anthropomorphic feelings about their spiders.
They often live their entire lives in a single burrow in the wild, rarely traveling outside of it while they wait for food to come to the entrance.
Based on the observations that people have made in the wild about tarantulas, as well as about specimens kept in hobby collections, it is a relatively safe assumption to say that they feel more secure in smaller enclosures.
If you give a tarantula a very spacious enclosure, then the majority of the cage space will go unused once they have settled into the area that they’ve chosen to be their hide.
Sometimes, it is beneficial to use larger than normal cages for spiders that either show they will utilize the entire space provided to them, or for ones that are known to be particularly bolty to give the keeper a slightly larger margin of error.

Are really big enclosures dangerous for tarantulas?
A large enclosure that is not filled with an appropriate depth of substrate for the height of the container can be dangerous for terrestrial species.
The spider can potentially rupture its abdomen if it falls from the top of a tall enclosure should it hit something hard or sharp.
Larger tanks, like 10-gallon aquariums, also often come with screen lids. It is best to avoid screen lids on tarantula enclosures because even the terrestrial species have a tendency to climb to the lid sometimes.
Tarantulas are known to get their toe claws stuck in the mesh, which usually ends with an amputated leg. Although a tarantula can grow back missing legs, it is better to just avoid the situation entirely.
Another potential drawback to giving a tarantula a lot of space is that the enclosure will be more difficult to maintain. Sometimes, tarantulas that are given too much extra room exhibit a less aggressive feeding response which can hinder growth.
How big of an enclosure do adult tarantulas need?
One general rule of thumb that hobbyists use is that the cage should be approximately two to three times the size of the diagonal leg span. Alternatively, some keepers prefer to pick enclosures that are three times the length and two times the width of the adult specimen.
The height of the enclosure is what is important for arboreal and fossorial species, while terrestrials need adequate width and depth for digging. Two-gallon tanks and five-gallon tanks work great for almost all species of tarantulas when they reach adulthood.
Alternatively, if you’re using a Kritter Keeper (or similar plastic containers) most terrestrial tarantulas will do fine in the large size as adults.
Why don’t tarantulas need a big cage?
In the wild, tarantulas rarely venture outside of their burrow. When they do it’s typically only a very short distance. The exception to this is mature males that begin roaming to look for a mate.
A tarantula that has an established burrow will only leave it if it needs to find food, there’s a flood during heavy rain, or if a predator flushes the spider out of the hole.
If you are keeping a terrestrial species, then just keep in mind that the larger the enclosure is the more substrate you will have to use.
Technically, you can put a Grammostola rosea in a 10-gallon tank. However, you will need to fill up the tank more than halfway full with substrate to ensure that the tarantula does not get hurt if it falls.
Do tarantulas need extra room in the cage to molt?
Tarantulas are very good at molting successfully in small spaces. You don’t have to overhaul the cage if you notice that your spider is in premolt.
Typically, the tarantula will spend some time prior to molting to enlarge their burrow or extend their web tube if they feel like it’s too confined. A proper set up will always allow the spider to excavate more or to add more webbing to their hammock.
However, you may need to rehouse them into a larger enclosure after they harden post-molt if the container was already looking a bit cramped.
Can a tarantula cage be too small for the spider?
The cage that you keep your tarantula in would be considered too small if it does not have enough room to adequately fit a decent hide for the size of the spider.
Additionally, a container can be too small if the spider barely has room to dig a burrow (for terrestrials and fossorial species) or to web around the top (for arboreals).
As long as your tarantula has enough room for a nice piece of cork bark, a small water dish, and enough substrate to retain soil moisture, then you’re probably doing everything correctly in terms of enclosure size.
Do you have to gradually increase the size of the cage as the tarantula grows?
Most new keepers that ask this question are wondering if they can just stick a small sling immediately into its permanent enclosure to avoid having to rehouse them.
In general, this isn’t a good idea. Tiny spiders are fully capable of escaping from ventilation holes in larger containers if the hole is larger than their carapace.
Slings and juveniles will be easier to feed when they are kept in smaller containers, and it will also be easier to maintain the proper soil moisture for them.
That being said, some hobbyists do use slightly larger than normal containers for each life stage to reduce the amount of interaction they have to have with the spider before it’s ready for its adult cage.
Final Thoughts on Tarantula Cage Size
In general, people new to the hobby tend to pick out enclosures that are too large for their tarantula based on prior experience with other animals. Tarantulas truly do not need a lot of room. Not only do they feel more secure in smaller space, but you will be able to monitor their feeding times more easily. That being said, adult tarantulas shouldn’t be kept in super tiny deli containers or anything ridiculous like that!