Ferguson zones
A 1 to 4 scale that groups species by how much UV they need, used to pick the right UVB.
The Ferguson zone system classifies reptiles by their natural sun exposure, from Zone 1 (shade-dwelling, crepuscular or nocturnal) to Zone 4 (open-sun baskers like uromastyx). It is the standard framework for choosing UVB strength and how close the animal should be able to get to the lamp.
A crested gecko (Zone 1) needs little to no UVB; a bearded dragon or tortoise (Zone 3 to 4) needs a strong tube across much of the enclosure. Matching the tube and its distance to the zone is what gets the dose right.
baskr turns the fundamentals into practice, log temperature, humidity and weight and it scores each animal against species ideal ranges, flagging problems early.
Start freeMore basics in the glossary, or jump to the health reference and care guides.
General husbandry guidance, not veterinary advice. Always confirm details for your species with an up-to-date care sheet, an experienced keeper or an exotics vet.