Corn Snake Temperatures & Humidity Requirements

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Because corn snakes are crepuscular/nocturnal, many say that lighting beyond the natural cycle of the lights in your house/reptile room is not required. This is incorrect. Just as there is bright daylight in the wild, corn snakes need a distinct day/night cycle in captivity as well.  Providing terrarium-specific lighting is very beneficial for regulating your snake’s natural biorhythms and encouraging natural behaviors. Your corn snake’s lights should be on 12 hours/day

Wild corn snakes are sometimes exposed to varying levels of UVB wavelengths during the day. Conventional wisdom dictates that UVB is not required for most snakes, BUT  — recent studies (especially work by Frances Baines) increasingly suggest that UVB can be very beneficial for a snake’s mental and physical health.

We at ReptiFiles strongly recommend providing UVB to all pet reptiles, including corn snakes. To include UVB in your husbandry, use a T5 HO UVB fluorescent tube like the Zoo Med Reptisun T5 HO 5.0 or Arcadia Forest 6% and replace every 12 months.

  • PRO TIP: If you use UVB, make sure that the fixture doesn’t have a piece of glass or plastic to “protect” the bulb. UVB rays are blocked by glass and plastic, rendering that bulb you just spent so much money on completely useless. Naked UVB bulbs are effective UVB bulbs! 

Nighttime lighting such as a colored bulb is not necessary and can actually disrupt your snake’s circadian rhythm (day/night cycle). Don’t waste your money. 


Corn snakes are reptiles, which means that they are cold-blooded. Cold-blooded animals rely on their environment to provide the warmth/heat their bodies need for proper metabolism.

Perfect corn snake temperatures are on a heat gradient, with 3 temperature zones across the terrarium. This enables to the snake to move between zones as is comfortable.

  • Basking surface: 90°F (32°C)
  • Ambient (air temp): 78-82°F (25-27°C)
  • Cool zone: 75°F (23-24°C)

Temps can safely fall to 68°F (20°C) at night, so night heat should be not be necessary. However if you need it, use a ceramic heat emitter or heat pad connected to a thermostat for safe use.

I recommend spending a quick $20 on a good temp gun like the Etekcity Lasergrip 774 for instant temperature readings anywhere you point it. (Don’t bother with a sticker or gauge-type thermometer — they’re useless.) 

This is one of the big reasons why it is important to set up your enclosure at least a week before bringing your corn snake home — getting corn snake temperatures in the right place can take some fiddling around, especially since different heat bulb wattages produce different temperature depending on a variety of factors such as enclosure height and room temperature.

How to heat your corn snake enclosure

Heat lamps

In nature, warmth comes from the sun (above), not from the ground (below). In fact, reptiles retreat underground to escape the sun and get cooler, not warmer. Providing warmth from below, as with a heat mat, is therefore unnatural and will promote unnatural behaviors. Heat lamps solve this problem by mimicking the effects of the sun and warming both the air and the ground below.

I recommend using a dome-style heat lamp fixture with a ceramic socket and a built-in lamp dimmer, like this one by Zoo Med.

As for the heat bulb,  there are many different types of heat bulbs on the market, from reptile-specific brands to ordinary bulbs at your local home improvement store. Reptile brand halogen bulbs can work well, but they tend to be short-lived. I’ve had the best experience with the Zoo Med Repti Basking Spot heat bulb and the Philips 100W Halogen Heat Lamp bulb.

What wattage? This is a common question with no solid answer, sorry! What wattage bulb you will need depends on room temperature, enclosure height, and other factors. What works for one person won’t always work for another, which is why I like lamp dimmers so much. When in doubt, try the higher-wattage bulb first. It’s also best to do your testing BEFORE you bring home your new snake.

  • Pro tip: Be sure to buy white or clear bulbs rather than red, blue, black, or whatever other color they’re offering. Colored bulbs often do more harm to a snake than good.

Alternatively, you can use a deep heat projector instead of a regular heat bulb. The Arcadia Deep Heat Projector represents a revolution in lightless heat sources, providing IR-A and IR-B, the two most effective forms of infrared (heat) at warming your pet all the way down to its muscles and organs. These wavelengths are the same ones produced by the sun, the kind of heat that reptiles have evolved to depend upon. This bulb is now available in the US, Canada, and the UK.

  • NOTE: The Deep Heat Projector must be connected to a proportional (dimming) thermostat like the Herpstat EZ1 or else it will get too hot for your snake.

If you are concerned about “belly heat,” placing a piece of flagstone or slate tile under the heat lamp will absorb warmth that your snake can curl up on. In fact, I recommend doing this anyway.

Heat mats

Heat mats are the still the most widely used method of maintaining correct temperatures for corn snakes, although I believe that they are an inferior heat source compared to heat lamps. Heat mats produce warmth without light, and are only good for heating the bottom of an enclosure, not the air. A common argument for heat mats is that they provide “belly heat,” which is supposedly more effective. However, this is not correct, and we only recommend using heat mats as a supplementary nighttime source of heat if necessary.

Choose a high-quality heat mat that will cover about 1/4 to 1/3 of the terrarium’s floor space. Trusted heat mat brands include Fluker’s and Ultratherm.

  • PRO TIP: If you are using a wood or melamine terrarium, place the heat mat INSIDE the enclosure underneath a thick layer of substrate. There should be no risk of your snake burning itself on the pad if you’re using a thermostat, but if you’re in Europe you can also experiment with the Vivexotic Heat Mat Holder.

Heat mats can only be safely used if paired with a thermostat, a device that regulates how hot the mat gets. These range in quality and price (lower price usually means lower quality), but if you only have one or two snakes, you can use the Exo Terra Thermostat as a low-cost option.


Heat rocks (also known as hot rocks/rock heaters/etc.) are manufactured and distributed under the same premise as an electric blanket — convenient heat whenever your reptile needs it. Sounds like a great idea, right? However, heat rocks are notoriously unreliable, and many a reptile has lost its life due to severe burns caused by these devices. Additionally, they’re not a good choice for heating your enclosure, as it only warms the rock’s surface, not the surrounding air.


Corn snakes thrive between 40-50% humidity. Correct humidity levels help maintain respiratory health as well as facilitate proper shedding.

Most corn snake keepers should be able maintain correct humidity with good substrate, a large water bowl, and little other effort. However, those who live in particularly dry climates may need to supplement this by placing the water bowl on the warm side of the terrarium (as opposed to the cool side) and misting as needed.

Keep track of your corn snake humidity levels with a hygrometer. My personal favorite is the Zoo Med Digital Thermoeter and Humidity Gauge.

Keep reading:

  1. Introduction to Corn Snakes
  2. Shopping List
  3. Terrarium Size & Lighting Guidelines
  4. Temperature & Humidity Requirements (YOU ARE HERE)
  5. Substrate Options
  6. How to Decorate Your Terrarium
  7. How (and What) to Feed a Corn Snake
  8. Handling Tips
  9. Common Diseases & Other Health Info
  10. Additional Resources