Is Your Baby Too Hot or Too Cold While Sleeping? Here’s How to Know…

safe sleep sleep clothing sleep environment sleep sacks sleep safety Mar 09, 2023
Is Your Baby Too Hot or Too Cold While Sleeping? Here’s How to Know…

When it comes to your little one’s sleep, I know how overwhelming it all can be. Even making sure your baby’s room is at an ideal temperature can feel like a lot! And anything to help take the guesswork out of baby sleep can be so helpful to make us parents feel more confident and at ease!

We’ve all been there… laying awake at night wondering if your little one is sweating or shivering in their bed (because maybe WE feel too hot or cold in our own bed), feeling unsure of the right move to make, AND not wanting to go disrupt our sleeping baby after they’ve been put down to check on their room temp. 

In particular, ensuring that your baby isn’t too hot is extremely important for safety reasons, as overheating has been linked with higher rates of SIDS (Sudden Infant Death Syndrome). Keep reading to get a solid gut check on how to figure out if your little one is sleeping safely and comfortably based on the temperature and what to do if you do find that they are either too hot or too cold in their current environment. 

How to Know if Your Baby is too Hot or Cold While Sleeping 

Before you begin troubleshooting, remember that your baby being too cold is always better than too hot, as overhearing is a risk factor for SIDS [1]. If your baby is too cold or uncomfortable, they will likely cry to let you know! 

The ideal temperature for the body to sleep well is between 68-72 degrees F, but if that’s not possible in your home or part of the world, that’s ok! Don’t stress - you can always adjust factors to ensure that your baby is comfortable. 

The best way to determine whether your baby is too hot or cold while sleeping and whether you should make adjustments is to wait 10-15 after your baby has fallen asleep, then touch your hand to their back or chest. Your baby’s hands and feet are not good indicators of warmth, so going off of the temperature of their back or chest is best! Your baby should feel slightly warm, but completely dry. If your baby feels cool to the touch or moist and sweaty whatsoever, you’ll want to make adjustments.

If your baby is too cold, here are some options you can choose to adjust based on your home or sleep situation:

  • Adjust the thermostat and re-check your baby’s temperature in another 10-15 minutes.
  • Use a space heater in the room for 20-30 minutes to warm the room up, but remember to turn it off before you go to sleep.
  • The safest and most effective option for the entire night is to add extra wearable layers to your child, like long sleeve pajamas instead of short sleeves, a onesie beneath their pajamas and sleep sack, a pair of socks, or an additional sleep sack, etc.

What NOT to do if your baby is too cold:

  • Do not add a head covering. They are NOT recommended by the AAP, as a hat could move/fall off while your baby is sleeping and become a potential hazard in your baby’s sleep space, and could lead to overheating [2]. 
  • Do not add extra loose blankets or sheets, unless your child is already out of the crib and sleeping in a bed, and is over 12 months old. Loose bedding and extra sheets (other than a tight-fitted sheet over the mattress of the crib) are a safety risk for strangulation, suffocation, and SIDS. 

If your baby is too hot, here are some options for adjustments you can make:

  • Immediately remove a layer of clothing, as this will be the fastest way to adjust their temperature for safety. 
  • Remove your baby’s sleep sack or swaddle. 
  • Adjust the thermostat, or consider using a fan if turning down the thermostat isn’t an option. 

Tips for Keeping Your Baby Safe While Sleeping

It can often be tricky keeping your baby at a comfortable temperature, or figuring out initially what temperature is best to keep your home/nursery at for safe sleep. Here are some easy-to-follow tips for keeping your little one safe while sleeping:

Don’t overlayer. If you do layer, avoid dressing your baby in more than 1 additional layer than you yourself would be comfortable wearing. Think of the sleep sack as taking the place of a blanket that you are under while sleeping. 

Avoid thick materials. If the room is cold, it’s best to layer a onesie (long or short sleeve), pajamas, and a sleep sack rather than clothes that would be best suited for outdoors. Avoid thick sweaters or other winter fabrics. Though, a fleece sleep sack could be a suitable option if your house tends to be rather cold.

Check the TOG of your baby’s sleepwear. TOG is a unit of thermal resistance that is used to measure the warmth of a fabric. Most infant pajamas range from 0.5 TOG (least warm) - 3 TOG (most warm). This number will often be listed on products, but if you’re unable to locate it, check the manufacturer's website. For example, a 1.5 TOG sleep sack is best suited for 68-72 degrees F and can be worn with a light pair of pajamas beneath. If you’re unsure about this, there are charts easily found on google that can help you when it comes to finding the best TOG for your baby in accordance with your home’s temperature. 

Pay close attention to signs of overheating. Check your baby’s core (back or chest) to make sure they are not at all sweaty. Also watch for their face becoming red, and for rapid breathing. 

There are instances when the temperature of our homes may be out of our control (your A/C or heater is no longer working, etc.). Here are a few additional tips for when your baby’s room won’t stay warm or cool enough for your baby to sleep soundly, as well as ways that you can prep for ways to heat up or cool down a room when unexpected instances pop up, like the power going out! 

If the room is too cold:

  • Run a space heater. If you choose to do this, remember that space heaters are a fire risk and should only be used while you are awake! Be sure to turn it off when the last person in your home goes to sleep. 
  • Put a thick rug on the floor. This is helpful if the room is over the garage and the cold air is coming up through the floor.
  • Use thick room darkening curtains. I recommend this anyway for great sleep, but most also help keep the room warmer.  
  • Try putting tinfoil on the windows for a quick fix. 

If the room is too hot:

  • Run a fan. If the fan is not cooling down the room efficiently, try placing a shallow bowl of ice, or ice packs behind the fan. 
  • Use thick room darkening curtains. I recommend this anyway for great sleep, but most also help keep the room cooler by keeping the sun out from the day. 
  • Try putting tinfoil on the windows for a quick fix. 

Even more important than helping your little one develop healthy sleep habits, is keeping them safe. Trust your parent gut! If your baby is dressed appropriately for their sleep environment and is comfortable, there is no need to stress. 

If you find yourself still struggling with your little one’s sleep, please know that you are not alone and that I am here to help. Download one of my comprehensive sleep guides! They’re broken up by age and provide step-by-step instructions on how to help your baby sleep longer and better over time. Or check out my 1-on-1 email support package for personalized troubleshooting guidance.





Need help transforming your child's sleep? Check out my sleep offerings for children 0-3 years old!


Want to receive updates from Baby Sleep Dr. straight to your email?

Join my mailing list to receive the latest news, blogs, and updates! Don't worry, your information will not be shared.

I hate SPAM. Your information, for any reason, will never be shared with a third party.