Tarantula Enclosure Size Calculator
Work out the safe floor space, height and substrate depth for your tarantula based on diagonal leg span and whether it is terrestrial, arboreal or fossorial.
Recommended enclosure
Floor space
15 × 11 in
Length × width minimum
Height
8 in
Keep low — falls are fatal
Substrate depth
4 in
Ventilation
Cross-flow
Cross-ventilation: two opposing side vents
- • Rehouse only when the spider has hardened after a moult (7-10 days).
- • Height above 1.5× leg span risks a fatal abdominal rupture from falls.
- • Always include a shallow water dish, regardless of species.
How it works
Hobbyist husbandry standards scale enclosure dimensions to diagonal leg span (DLS). Terrestrial species need roughly 3× DLS of floor length with height capped near 1.5× DLS because falls rupture the abdomen. Arboreal species invert that ratio — around 4× DLS of height with vertical cork bark. Fossorial species need deep substrate, about 2.5× DLS, so they can construct a stable burrow.
Examples
- 5" terrestrial Brachypelma≈ 15" × 10" floor, 7" tall, 4" substrate
- 4" arboreal Avicularia≈ 8" × 6" floor, 16" tall, 2" substrate