This tool provides a general estimate and does not replace professional veterinary advice.
Updated · How we check our tools
What is the Tarantula Enclosure Size Calculator?
The Tarantula Enclosure Size Calculator recommends minimum enclosure size for tarantulas based on adult size. Undersized housing is one of the most common and most fixable welfare problems in pet keeping, it affects everything from stress levels to exercise to litter/waste management.
Tarantulas generally live 10-25 years when they are well looked after. As an insectivore, what a tarantula needs from its diet changes across its life stages. Terrestrial species need more floor space than height, with substrate deep enough to burrow and no more than 1.5 times their leg span of climbing room, since a fall can rupture the abdomen. Keep an eye out for fall injury from over-tall enclosures, dehydration, failed molt. These are the conditions tarantulas are most commonly seen for.
Tarantula quick facts
| Measure | Tarantula |
|---|---|
| Typical lifespan | 10–25 years |
| Adult weight | 0.7–5.3 oz (20–150 g) |
| Diet | Insectivore |
| Mature at | About 3 years |
| Clutch size | 50–2000 eggs |
| Humidity | 65–75% |
How does the Tarantula Enclosure Size Calculator work?
The recommendation is based on published care-guide minimums for tarantulas, scaled to the animal's current or expected adult size. Treat the result as a well-founded estimate. Every tarantula is an individual, and your vet's judgement outranks any online tool.
Factors that matter
- Adult size: housing should be sized for the animal's full-grown dimensions, not its current size if still young
- Number of animals being housed together, since space needs don't simply divide evenly
- Activity level and natural behavior, such as climbing, digging or swimming space
- Whether the space is temporary (travel/carrier) or permanent (everyday housing)
How do you use the Tarantula Enclosure Size Calculator?
- Enter the adult weight in whichever unit you use (lb, oz, kg)
- Enter the nose-to-tail length in whichever unit you use (in, ft, cm)
- Answer "How many animals share this space?"
- Pick your time spent in the enclosure (Only to sleep, Part of the day, Most of the day, ...)
- Press Calculate, then read the result alongside the sources listed below
If two people care for your tarantula, agree on one method and stick to it. Half of all confusing results come from measuring differently each time.
For related questions, see the other housing tools or browse every tarantula tool.
Before you rely on this
Averages hide a lot of variation. The figure here reflects what is typical for tarantulas, but your tarantula may sit well outside it for perfectly ordinary reasons. Use the result to spot changes over time in your own animal rather than to compare it against other people's pets.
Sources and references
The formulas, reference ranges and species data behind the Tarantula Enclosure Size Calculator come from these veterinary references, professional bodies and published research.
- Built on veterinary referencesFormulas and ranges come from veterinary manuals, university research and welfare bodies, listed above for you to check.
- Instant resultsNo page reload, no waiting and no account. Enter your details and the result appears straight away.
- Private by designCalculations run in your browser. Nothing you enter is stored on our servers or shared with anyone.
- Always freeEvery XpertsPet tool is free to use, with no premium tier and nothing to sign up for.