Best Temperature for Sleeping Baby (2024)

Last updated: October 2, 2023 by Nicole Johnson, B.A., M.B.A., Lead Pediatric Sleep Consultant

When my son was a baby, he was a terrible sleeper. Even when he was in Elementary school, he was still not a perfect sleeper. I grew to accept that until he became a teenager when I had to drag him out of bed. My son was sensitive to schedule and routine changes and was, in general, a light sleeper. What I later figured out was that he was also sensitive to the room temperature and what he was wearing. In this post, I share the best temperature for a sleeping baby after much research and 15+ years as a sleep consultant.

Temperature and Sleep

When my son was a toddler, I realized that the same night he started waking up at night again was when we had put thermals on underneath his fleece footed PJ’s. Because it was so freezing outside and we were worried about him being cold, we over-compensated. As parents, we often worry about our children being too cold but this can often cause more sleep problems than it solves! And, boy, was I happy to figure it out! You’d think your toddler would say, “Mommy, I’m too hot,” but they simply don’t always realize what’s waking them up. So, I did some homework so I could pass on the best temperature for your baby or toddler’s room when they sleep. Hopefully, my experience again will help others.

Temperature and SIDS

It is very important that you not overheat your newborn when they sleep as it increases the risk of SIDS.

Body Temperature

Our internal body clock controls our body temperature and when our temperature is high, like during the day, our bodies are more awake. We all have a dip in body temperature in the afternoon and we feel sleepy (Ferber calls this the “afternoon dip”). At night, when the sun goes down, our body temperature starts to drop and the hormone Melatonin is released in our bodies inducing sleep.

Our body temperature is lowest at night until around 4 a.m. our bodies start to prepare to wake up. Many parents complain about early waking. It’s the lightest sleep of the night.

What Temperature to Set Your Thermostat?

The best room temperature for a sleeping baby is between 65 and 70 degrees Fahrenheit (or 18.3 to 21.1 Celsius), but I recommend you use these numbers as a starting point. In my experience of 15+ years as a sleep consultant, the best temperature for your family will vary a little, depending on you (and your baby) and how many blankets you use. Keep in mind that your child won’t learn to keep a cover on all night until over 18-24 months.

With the air conditioning on, 72 degrees can feel cold whereas if you put your thermostat to 72 with the heater, it will probably be too hot. In the summer, at night, my family keeps our thermostat at 72 degrees Fahrenheit and during the winter we set it to 63 degrees Fahrenheit. Your baby or toddler’s skin should feel cool to the touch, but not frigid like their fingers are ice cubes. And, generally, your child should never be sweating.

For my youngest, we put on a onesie t-shirt, thermal pajamas, and then fleece pajamas over those this winter. For my eldest, we put just Fleece footed pajamas and to go with his sheet and comforter. In the summer, generally, pajamas and a sleep sack (or sheet and comforter) are sufficient.

If our body temperature being higher in the day keeps us awake, I would venture to guess that my son was waking up partially because his body temperature was too high as much as it was because he may or may not have been uncomfortable. The moral of the story is to keep the kids warm, but not too warm, and not too cold, either, yet another parenting magic trick!

Is 78 Degrees Too Hot for Baby to Sleep?

Yes, in my experience, 78 degrees is too hot for a baby to sleep well both in the summer and the winter. Overheating can also increase the risk of SIDS so can be unsafe. Ideally, the room temperature will be between 68 and 70 degrees. If you live in a warm climate, 72 to 74 degrees may work but you must not overdress your baby if you want them to sleep.

Is 80 Degrees Too Hot for Baby to Sleep?

Yes, again, 80 degrees is likely much too hot for your baby to sleep well. At 80 degrees, they are likely sweating through their pajamas and onto their sheets. When the sheets are wet, you can be even more uncomfortable!

Is 74 Degrees Too Hot for Baby to Sleep?

It is possible 74 degrees is comfortable enough for your baby to sleep but if they feel warm to the touch, you may want to dress them lighter, use a lighter sleep sack, or reduce the temperature of the house. At 74 degrees, it’s borderline.

One final thing to keep in mind is that in my family of four, two of us are extra sensitive to temperature but we all sleep poorly when the room temperature is TOO HOT. You might need to experiment with what the best temperature is for your particular baby since some of us run hotter than others. I hope this article will help you find the best temperature for your baby’s sleep!