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Why every heat source needs one
Heat mats, bulbs and heat projectors don't know how warm your enclosure is. Room temperature changes through the day and the seasons, so a setup that's perfect in winter can overheat in summer. A thermostat reads a probe in the enclosure and controls the heat to keep it at your set temperature. Thermal burns from unregulated heat are one of the most common reptile injuries, and a thermostat prevents them.
The three types
| Type | How it works | Best for |
|---|---|---|
| Dimming | Lowers power to the bulb to hold temperature | Halogen and incandescent basking bulbs |
| On/off | Switches power fully on or off at the set point | Heat mats, deep heat projectors, ceramic heat emitters |
| Pulse-proportional | Rapidly pulses power for very stable temps | Heat mats, ceramic emitters, radiant panels (not light bulbs) |
Rule of thumb: if it makes light, use a dimming thermostat. If it makes heat only, on/off or pulse both work, with pulse being more precise.
Our picks
Herpstat thermostat
Proportional and dimming modes, high/low alarms and multiple outlets. Built for serious keepers and big setups.
Inkbird reptile thermostat
Affordable digital thermostats with day/night settings; check you choose the dimming or on/off model that matches your heat source.
Where to put the probe
- Basking bulbs: put the probe at or just above the basking surface, secured so the animal can't move it.
- Heat mats: put the probe on the substrate surface directly above the mat, or between mat and enclosure floor per the manufacturer's guidance.
- Overhead heat for snakes: probe at the warm hide or basking surface.
Always confirm with a separate thermometer. An infrared temperature gun is the easiest way to check basking surfaces.
Thermostat safety checklist
- Match the thermostat type to the heat source.
- Check the thermostat's wattage rating is above your heat source's wattage.
- Secure the probe so it can't be knocked out of place. A probe on the floor can let the heat run full blast.
- Use day/night settings if your species benefits from a nighttime drop.
- Check temperatures daily for the first week, then regularly after that.
See how heating fits into the full setup in our beginner setup checklist.
FAQ
Do I really need a thermostat for a heat mat? Yes. Unregulated heat mats regularly burn reptiles.
Can I use an on/off thermostat with a basking bulb? It works, but a dimming thermostat is the better match for light-emitting bulbs.