Temperatures below 60°F (16°C) are too cold for a leopard gecko and pose a serious health risk. Even brief exposure to temperatures in this range can stress their body, and sustained cold can lead to respiratory infections, digestive shutdown, and worse. Understanding the safe temperature range, and what to do when things get too cold, is essential to keeping your gecko healthy.
The Safe Temperature Range
Leopard geckos need a temperature gradient in their enclosure, with a warm side and a cool side so they can regulate their own body heat. During the day, the warm basking spot should sit between 88°F and 92°F (31–33°C), while the cool side should stay around 75°F to 80°F (24–27°C). This gradient lets your gecko move between warmer and cooler zones as it needs to.
At night, temperatures can safely drop to around 70°F (21°C), which mimics the natural cooling that would happen in their native habitat across arid parts of the Middle East and South Asia. Some sources note that leopard geckos can tolerate nighttime drops as low as 60°F (16°C), but this is the absolute floor, not a target. Anything below 60°F is dangerous territory. The safest approach is to keep nighttime lows at or above 70°F and treat anything below that as a warning sign that your heating setup needs attention.
What Cold Does to a Leopard Gecko’s Body
Leopard geckos are ectotherms, meaning they depend entirely on their environment for body heat. When temperatures drop too low, their metabolism slows dramatically. Digestion is one of the first systems affected. Food sitting undigested in a cold gecko’s stomach can actually rot, leading to bacterial infections in the gut. This is why many experienced keepers recommend not feeding a gecko whose enclosure has been too cold until temperatures are restored.
The immune system also takes a hit. Respiratory infections are one of the most common and dangerous consequences of cold exposure in reptiles. These infections are closely linked to environments that are consistently kept in the low 70s°F or that experience occasional sharp drops to much lower temperatures. The risk compounds when other stressors are present, like a poor diet or unsanitary conditions. A gecko that’s already slightly stressed from one factor becomes far more vulnerable when cold is added to the equation.
Signs Your Gecko Is Too Cold
Cold stress doesn’t always look dramatic at first. The earliest sign is usually a drop in activity. Your gecko may stop moving around the enclosure, spend all its time pressed against or on top of the warm hide, and show little interest in food. Lethargy that lasts more than a day or two, especially paired with a temperature check that reveals low readings, is a strong signal.
As cold exposure continues, more serious symptoms appear. Watch for:
- Wheezing or clicking sounds when your gecko breathes, which suggest a respiratory infection is developing
- Nasal discharge, sometimes visible as bubbles around the nostrils
- Refusal to eat for several days in a row
- Unusual color changes, particularly a duller or darker appearance than normal
A respiratory infection in a reptile doesn’t resolve on its own. If you notice wheezing or discharge, your gecko needs veterinary care from a reptile-experienced vet.
How to Monitor Temperatures Accurately
A single thermometer stuck to the glass wall of the enclosure won’t give you the reading that matters most. Leopard geckos are ground-dwelling animals, so the temperature at floor level is what counts. A digital thermometer with a probe placed directly on the substrate under the heat source gives you the most accurate warm-side reading. An infrared temperature gun is also useful for spot-checking different areas of the enclosure quickly.
If you’re using a heat mat (the most common heat source for leopard geckos), the thermostat probe should sit on the inside surface of the enclosure floor, directly above the mat. This lets the thermostat measure the actual surface temperature your gecko will feel when it lies on that spot. Without a thermostat, heat mats can overheat and cause burns, or cycle off and leave the enclosure too cold. A thermostat isn’t optional; it’s the most important piece of equipment after the heat source itself.
Place a second thermometer on the cool side so you can verify the gradient. Checking both readings daily takes seconds and catches problems before your gecko shows symptoms.
Nighttime Heating Solutions
If your home drops below 70°F at night, especially in winter, your gecko needs supplemental nighttime heat. A ceramic heat emitter is the most popular option. It produces heat without light, which is important because leopard geckos are crepuscular (most active at dawn and dusk) and bright light at night disrupts their natural cycle. Colored “night bulbs” marketed for reptiles can actually disturb their rest, so avoid those.
A ceramic heat emitter mounted on one side of the enclosure, controlled by a thermostat, maintains the warm side without overheating the cool side. Deep heat projectors work the same way and are another good option. Either one plugged into a thermostat set to around 75°F will keep nighttime temperatures in a safe range without requiring you to adjust anything manually.
What to Do During a Power Outage
Power outages in cold weather are the most common emergency scenario for gecko owners. Without electricity, your heat source stops working and the enclosure will gradually cool to room temperature, then potentially lower. You have a window of time, but you need to act before temperatures fall into the danger zone.
The first priority is insulation. Wrap the enclosure in towels or blankets on all sides to trap whatever warmth remains inside. This alone can slow heat loss significantly, buying you hours in a moderately cool house. If you have disposable hand warmers (the kind sold for winter sports), activate one or two and place them near the outside of the enclosure or wrapped in a sock inside the enclosure. Never place an unwrapped hand warmer directly against your gecko, as they can reach temperatures high enough to cause burns. Monitor the temperature inside the enclosure with your thermometer to make sure the hand warmers aren’t overheating one spot.
If the outage is prolonged and you have no other heat source, holding your gecko against your body under a layer of clothing can keep it warm through skin contact. Your body temperature of around 98°F is within a safe range for a gecko, especially compared to a rapidly cooling enclosure. This is a last resort, but it works in a genuine emergency.
Once power returns, bring the enclosure back up to temperature gradually rather than blasting it with extra heat all at once. Wait until temperatures are fully stabilized before offering food, since a gecko whose body temperature has dropped significantly won’t be able to digest properly.