Minimum size calculator
Calculate the minimum terrarium size under Swiss law
How big does the terrarium for your corn snake, ball python or bearded dragon have to be at least? Choose the species and enter the body length and the number of animals. The calculator gives length, width and height under Annex 2 of the Animal Welfare Ordinance and, where it does not list the species, under the expert report the ordinance names as a guide.
Minimum size calculator
Choose a species, then enter the body length.
How the calculator works
First the Animal Welfare Ordinance
If Annex 2, Table 5 (reptiles) or Table 6 (amphibians) of the Animal Welfare Ordinance lists the species, the calculator uses only that line. The table gives no centimetres but multiples of body length, and mostly applies to up to two animals; for each further animal it requires a surcharge. If a reptile’s height would come out above 2.2 m, it may be capped at 2.2 m provided the floor area grows accordingly (preliminary remark A). For amphibians the height is an average. Table as of 1 February 2026.
Then the expert report as a guide
For species the table does not list, the general rule in Annex 2 (letter K) applies: the enclosure must be large enough for everything the species needs (hides, basking spot, climbing branches) to be arranged sensibly; expert reports based on scientific knowledge serve as a guide. For this the calculator uses the German expert report on minimum requirements for keeping reptiles of 10 January 1997. It is not a law but a recommendation. It refers to the snout-vent length for lizards, the total length for snakes and the carapace length for tortoises and turtles, caps the height at 2 m and sets surcharges in percent: for lizards 15 % floor area per additional animal, for snakes 20 % volume, for tortoises and turtles 10 % each for the third and fourth animal and 20 % each from the fifth.
What the calculator does not know
For species listed in neither the table nor the report it gives no figure: an estimate could not be backed up to anyone. On this website that applies to: African fat-tailed gecko, Chinese fire-bellied newt, False tomato frog, Oriental fire-bellied toad, Tomato frog, and White's tree frog. It does not check furnishing, climate or water quality. It works out a water section but does not compare it with your pool. The Animal Welfare Ordinance does not cover tarantulas, scorpions and insects. All values are rounded up: lengths to whole centimetres, areas to 0.01 m².
As in the app
The table, the assignment of species and the check of each dimension are the same as in ReptiCare’s TSchV check (checking the terrarium size against the Animal Welfare Ordinance). The app states the surcharge for further animals as a sentence; the calculator includes it.
All species in the calculator
72 species: 50 under Table 5 or 6 of the Animal Welfare Ordinance, 22 under the expert report as a guide.
Show the list with formulas
Snakes
| Species | Basis | At least |
|---|---|---|
| African house snakeBoaedon fuliginosus | 1997 expert report | 1 × 0.5 × 0.5 body lengths (length × width × height) |
| Amazon tree boaCorallus hortulanus | Table 5 TSchV, item 43b | Floor area 1 × 0.5 body lengths, height 0.75 body lengths |
| Amur rat snakeElaphe schrenckii | 1997 expert report | 1 × 0.5 × 1 body lengths (length × width × height) |
| Ball pythonPython regius | Table 5 TSchV, item 43a | Floor area 1 × 0.5 body lengths, height 0.75 body lengths |
| Beauty rat snakeElaphe taeniura | 1997 expert report | 1 × 0.5 × 1 body lengths (length × width × height) |
| Black kingsnakeLampropeltis nigra | 1997 expert report | 1 × 0.5 × 0.5 body lengths (length × width × height) |
| Blood pythonPython brongersmai | Table 5 TSchV, item 43a | Floor area 1 × 0.5 body lengths, height 0.75 body lengths |
| Boa constrictor | Table 5 TSchV, item 43a | Floor area 1 × 0.5 body lengths, height 0.75 body lengths |
| Brazilian rainbow boaEpicrates cenchria | Table 5 TSchV, item 43a | Floor area 1 × 0.5 body lengths, height 0.75 body lengths |
| Burmese pythonPython bivittatus | Table 5 TSchV, item 42 | Floor area 1 × 0.5 body lengths, height 0.75 body lengths |
| California kingsnakeLampropeltis californiae | 1997 expert report | 1 × 0.5 × 0.5 body lengths (length × width × height) |
| Carpet pythonMorelia spilota | Table 5 TSchV, item 43a | Floor area 1 × 0.5 body lengths, height 0.75 body lengths |
| Common garter snakeThamnophis sirtalis | 1997 expert report | 1.25 × 0.75 × 0.5 body lengths (length × width × height) |
| Corn snakePantherophis guttatus | 1997 expert report | 1 × 0.5 × 1 body lengths (length × width × height) |
| Emerald tree boaCorallus caninus | Table 5 TSchV, item 43b | Floor area 1 × 0.5 body lengths, height 0.75 body lengths |
| Gopher snakePituophis catenifer | 1997 expert report | 1 × 0.5 × 0.75 body lengths (length × width × height) |
| Green tree pythonMorelia viridis | Table 5 TSchV, item 43b | Floor area 1 × 0.5 body lengths, height 0.75 body lengths |
| Javelin sand boaEryx jaculus | Table 5 TSchV, item 43a | Floor area 1 × 0.5 body lengths, height 0.75 body lengths |
| Kenyan sand boaEryx colubrinus | Table 5 TSchV, item 43a | Floor area 1 × 0.5 body lengths, height 0.75 body lengths |
| Madagascar tree boaSanzinia madagascariensis | Table 5 TSchV, item 43a | Floor area 1 × 0.5 body lengths, height 0.75 body lengths |
| Mandarin rat snakeEuprepiophis mandarinus | 1997 expert report | 1 × 0.5 × 1 body lengths (length × width × height) |
| Mexican kingsnakeLampropeltis mexicana | 1997 expert report | 1 × 0.5 × 0.5 body lengths (length × width × height) |
| Milk snakeLampropeltis triangulum | 1997 expert report | 1 × 0.5 × 0.5 body lengths (length × width × height) |
| Reticulated pythonMalayopython reticulatus | Table 5 TSchV, item 42 | Floor area 1 × 0.5 body lengths, height 0.75 body lengths |
| Sumatran short-tailed pythonPython curtus | Table 5 TSchV, item 43a | Floor area 1 × 0.5 body lengths, height 0.75 body lengths |
| Western diamondback rattlesnakeCrotalus atrox | Table 5 TSchV, item 55 | Floor area 1 × 0.5 body lengths, height 0.5 body lengths |
| Western hognose snakeHeterodon nasicus | 1997 expert report | 1 × 0.5 × 0.5 body lengths (length × width × height) |
| Western rat snakePantherophis obsoletus | 1997 expert report | 1 × 0.5 × 1 body lengths (length × width × height) |
Lizards
| Species | Basis | At least |
|---|---|---|
| Argentine black and white teguSalvator merianae | Table 5 TSchV, item 27 | Floor area 5 × 3 body lengths, height 3 body lengths |
| Blue-tongued skinkTiliqua scincoides | Table 5 TSchV, item 28 | Floor area 7 × 4 body lengths, height 3 body lengths |
| Central bearded dragonPogona vitticeps | Table 5 TSchV, item 20 | Floor area 5 × 4 body lengths, height 4 body lengths |
| Chinese water dragonPhysignathus cocincinus | Table 5 TSchV, item 19 | Land section 5 × 3 body lengths, height 5 body lengths, plus water section 2 × 2 at 1 body length depth |
| Common collared lizardCrotaphytus collaris | 1997 expert report | 6 × 4 × 4 body lengths (length × width × height) |
| Fire skinkMochlus fernandi | 1997 expert report | 4 × 4 × 5 body lengths (length × width × height) |
| Gila monsterHeloderma suspectum | Table 5 TSchV, item 35a | Floor area 4 × 3 body lengths, height 2 body lengths |
| Green anoleAnolis carolinensis | Table 5 TSchV, item 17a | Floor area 6 × 6 body lengths, height 8 body lengths |
| Green iguanaIguana iguana | Table 5 TSchV, item 16 | Floor area 4 × 3 body lengths, height 4 body lengths |
| Rankin's dragonPogona henrylawsoni | Table 5 TSchV, item 20 | Floor area 5 × 4 body lengths, height 4 body lengths |
| Ridge-tailed monitorVaranus acanthurus | 1997 expert report | 5 × 2 × 2 body lengths (length × width × height) |
| Saharan spiny-tailed lizardUromastyx geyri | Table 5 TSchV, item 23 | Floor area 5 × 4 body lengths, height 3 body lengths |
| Savannah monitorVaranus exanthematicus | Table 5 TSchV, item 36 | Floor area 5 × 3 body lengths, height 2 body lengths |
| Schneider's skinkEumeces schneiderii | Table 5 TSchV, item 28a | Floor area 7 × 4 body lengths, height 3 body lengths |
Geckos
| Species | Basis | At least |
|---|---|---|
| Crested geckoCorrelophus ciliatus | 1997 expert report | 6 × 6 × 8 body lengths (length × width × height) |
| Gargoyle geckoRhacodactylus auriculatus | 1997 expert report | 6 × 6 × 8 body lengths (length × width × height) |
| Giant day geckoPhelsuma grandis | Table 5 TSchV, item 32 | Floor area 6 × 6 body lengths, height 8 body lengths |
| Gold dust day geckoPhelsuma laticauda | Table 5 TSchV, item 32 | Floor area 6 × 6 body lengths, height 8 body lengths |
| Leopard geckoEublepharis macularius | Table 5 TSchV, item 31 | Floor area 6 × 6 body lengths, height 2 body lengths |
| Neon day geckoPhelsuma klemmeri | Table 5 TSchV, item 32 | Floor area 6 × 6 body lengths, height 8 body lengths |
| New Caledonian giant geckoRhacodactylus leachianus | 1997 expert report | 6 × 6 × 8 body lengths (length × width × height) |
| Sarasin's giant geckoCorrelophus sarasinorum | 1997 expert report | 6 × 6 × 8 body lengths (length × width × height) |
| Tokay geckoGekko gecko | 1997 expert report | 6 × 6 × 8 body lengths (length × width × height) |
Chameleons
| Species | Basis | At least |
|---|---|---|
| Bearded pygmy chameleonRieppeleon brevicaudatus | Table 5 TSchV, item 15 | Floor area 6 × 4 body lengths, height 4 body lengths |
| Carpet chameleonFurcifer lateralis | Table 5 TSchV, item 13 | Floor area 5 × 3 body lengths, height 5 body lengths |
| Panther chameleonFurcifer pardalis | Table 5 TSchV, item 13 | Floor area 5 × 3 body lengths, height 5 body lengths |
| Veiled chameleonChamaeleo calyptratus | Table 5 TSchV, item 13 | Floor area 5 × 3 body lengths, height 5 body lengths |
Tortoises and turtles
| Species | Basis | At least |
|---|---|---|
| African spurred tortoiseCentrochelys sulcata | Table 5 TSchV, item 2 | Floor area 8 × 4 body lengths |
| Common musk turtleSternotherus odoratus | Table 5 TSchV, item 8 | Land section 2 × 2 body lengths, plus water section 4 × 3 at 1 body length depth |
| Greek tortoiseTestudo graeca | Table 5 TSchV, item 4 | Floor area 8 × 4 body lengths |
| Hermann's tortoiseTestudo hermanni | Table 5 TSchV, item 4 | Floor area 8 × 4 body lengths |
| Horsfield's tortoiseTestudo horsfieldii | Table 5 TSchV, item 4 | Floor area 8 × 4 body lengths |
| Marginated tortoiseTestudo marginata | Table 5 TSchV, item 4 | Floor area 8 × 4 body lengths |
| Painted turtleChrysemys picta | Table 5 TSchV, item 9 | Land section 2 × 2 body lengths, plus water section 5 × 3 at 2 body lengths depth |
| Red-footed tortoiseChelonoidis carbonarius | Table 5 TSchV, item 3 | Floor area 8 × 4 body lengths |
| Reeves' turtleMauremys reevesii | 1997 expert report | Length 5 carapace lengths, width half of that; the report sets no height |
Amphibians
| Species | Basis | At least |
|---|---|---|
| African clawed frogXenopus laevis | Table 6 TSchV, item 5 | Water section 6 × 4 at 4 body lengths depth |
| AxolotlAmbystoma mexicanum | Table 6 TSchV, item 13 | Water section 4 × 2 at 2 body lengths depth |
| Cranwell's horned frogCeratophrys cranwelli | Table 6 TSchV, item 2a | Floor area 10 × 5 body lengths, height 4 body lengths |
| Dyeing poison dart frogDendrobates tinctorius | Table 6 TSchV, item 3 | Floor area 25 × 15 body lengths, height 8 body lengths |
| Mimic poison dart frogRanitomeya imitator | Table 6 TSchV, item 4 | Floor area 20 × 10 body lengths, height 25 body lengths |
| Ornate horned frogCeratophrys ornata | Table 6 TSchV, item 2a | Floor area 10 × 5 body lengths, height 4 body lengths |
| Red-eyed tree frogAgalychnis callidryas | Table 6 TSchV, item 2 | Floor area 10 × 5 body lengths, height 10 body lengths |
| Yellow-banded poison dart frogDendrobates leucomelas | Table 6 TSchV, item 3 | Floor area 25 × 15 body lengths, height 8 body lengths |
Common questions
How big does a corn snake’s terrarium have to be?
The Animal Welfare Ordinance does not list the corn snake. The general rule in Annex 2 (letter K) then applies, and the 1997 expert report serves as the guide: at least 1 × 0.5 × 1 total lengths for up to two animals. A corn snake of 140 cm therefore needs at least 140 × 70 × 140 cm.
How big does a terrarium for a ball python have to be?
TSchV, Annex 2, Table 5, item 43a: floor area of 1 × 0.5 total lengths and height of 0.75 total lengths, for up to two animals. A ball python of 120 cm therefore needs at least 120 × 60 × 90 cm. For each additional animal, add 0.5 × 0.2 total lengths of floor area.
Are the minimum dimensions binding?
The values in Annex 2 of the Animal Welfare Ordinance are a legal minimum: the enclosure may not be smaller. For species the ordinance does not list, the expert report is a guide, not a law. In each case the cantonal veterinary office has the final say. And an enclosure that only just reaches the minimum is allowed, but not good for that reason.
Non-binding guidance without guarantee. The competent authority is authoritative.
