\u2190 The Tally Forge

Reptile Heating Calculator

A rough starting-point basking wattage by enclosure size — always confirm with a thermostat.

Reptile heating gear

Keep the gradient right: reptile thermostat, basking bulb, temperature gun.

As an Amazon Associate, The Tally Forge earns from qualifying purchases.

What Wattage Basking Bulb for a Reptile?

Reptile heating can't be reduced to a single number, because the right basking temperature depends entirely on the species — a bearded dragon wants a hot desert basking spot while a crested gecko needs it cool. This tool gives only a rough wattage starting point by enclosure size, to be dialed in with equipment, not trusted blindly.

Why species comes first

Before wattage, look up your specific animal's basking and cool-side temperature targets and its UVB needs. A bulb that's perfect for one reptile can cook or chill another. The enclosure's size, screen vs. glass, and room temperature all shift the wattage needed to hit those targets.

Thermostats and thermometers are non-negotiable

Never run a heat source without a thermostat controlling it — bulbs and mats can overshoot and harm your animal. Verify the actual basking-spot and cool-side temperatures with a probe or infrared thermometer, and adjust bulb wattage or height until the measured gradient matches your species' requirements. The number here is a guess; your thermometer is the truth.

Frequently asked questions

What wattage bulb does my reptile need?
It depends on the species' target temperatures and your enclosure — use this as a rough start, then adjust to measured temps.
Do I need a thermostat?
Yes, always. Uncontrolled heat sources can overheat and injure reptiles.
How do I check basking temperature?
With a probe or infrared thermometer aimed at the basking spot, adjusting the bulb until it matches your species' range.