Cohabitation Compatibility Checker

Whether an animal can be safely housed with another — of the same or a different species — is one of the questions this site gets asked about most often, and the honest answer varies enormously: some species (Syrian hamsters, most tarantulas) are strictly solitary and will fight or cannibalize a tankmate; others (guinea pigs) are genuinely harmed by long-term solitary housing and need a compatible companion.

This tool takes one or two species selections and returns each species' own sourced cohabitation guidance — solitary-only, same-species-group-compatible, or otherwise — pulled directly from the husbandry data published on that species' care page. Select a single species to see its own group-housing guidance, or add a second species to see the cross-species compatibility position.

The tool is deliberately honest about a limitation: reputable sources don't publish a specific verdict for every possible cross-species pairing, and inventing one would mean guessing at something with real welfare stakes. Where two different species are selected, the tool shows the general, widely-held welfare position (different species typically shouldn't share an enclosure, given differing environmental needs and disease-transmission risk) alongside each species' own sourced guidance, rather than fabricating a specific joint verdict.

Why this needs care rather than a simple lookup table: cohabitation compatibility sometimes depends on more than just species — sex ratio, enclosure size, and individual temperament can all matter even within a species that's broadly described as group-compatible. Where a species' sourced guidance flags this kind of nuance, it's shown directly in the result rather than flattened into a bare yes/no.

A related question worth asking before adding any second animal: is the current enclosure sized for two? The sourced minimum enclosure sizes on this site (see the Enclosure Size Calculator) are almost always calculated for one adult animal — a species that tolerates group housing in general still needs proportionally more space for each additional individual, not the same footprint stretched across more animals.

If you're introducing a new animal rather than asking a general compatibility question, pair this tool with the Quarantine Timeline Planner — even a genuinely compatible pairing should go through a full quarantine period before being introduced, since compatibility and disease safety are two separate questions.