Is My Baby Too Hot or Cold While Sleeping?
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As a parent, one of the most common (and valid) concerns I hear is:
"How do I know if my baby is too hot or too cold while they’re sleeping?"
Newborns can’t tell us when they’re uncomfortable. And since their temperature regulation system is still developing, they can overheat—or get chilled—faster than adults. Add in swaddles, sleep sacks, and seasonal temperature swings, and it’s no wonder parents second-guess themselves at bedtime.
Here’s how to check your baby’s temperature without overthinking it, plus tips to help you create a safe and cozy sleep environment year-round.
🌡️ Why Temperature Matters for Baby Sleep (and Safety)
Babies sleep best when they’re comfortably warm—but not too hot.
Overheating is a known risk factor for SIDS (Sudden Infant Death Syndrome), so it’s important to be cautious with layers and room temperature.
Too cold? Your baby may be uncomfortable and have disrupted sleep.
Too hot? Your baby may be at risk and also struggle to settle or stay asleep.
👶 How to Check If Baby Is Too Hot or Too Cold
Don’t rely on their hands or feet — babies often have cold hands or feet even when they’re perfectly warm.
Instead, use the core temperature check:
✅ Touch the back of their neck, chest, or tummy.
If it feels warm and dry, your baby is likely comfortable.
If it feels sweaty, hot, or clammy, your baby may be too warm.
If it feels cool to the touch, your baby may be chilly.
❄️ Signs Baby May Be Too Cold
Cool chest or tummy when you touch them
Cold hands + shivering or stiff limbs (though newborns rarely shiver)
Fussing, restlessness, or frequent wake-ups
A sleepy baby who won’t settle, even after feeding
🔥 Signs Baby May Be Too Hot
Sweaty head or damp hair
Flushed cheeks or red skin
Rapid breathing or heat rash
Lethargy or irritability
Baby feels hot to the touch, especially on chest or back
If your baby is overheated, remove a layer and adjust the room temperature. Never use fans directly pointed at baby, but do aim for airflow and ventilation.
🛏️ How to Dress Baby for Sleep (The “One More Layer” Rule)
A good rule of thumb:
Dress your baby in one more layer than what you’d wear to be comfortable in the same room.
For example:
Room feels cool? You might sleep in PJs + a light blanket → baby wears footie pajamas + a swaddle or sleep sack
Room feels warm? You might sleep in a t-shirt → baby wears a onesie or light cotton sleeper without an extra layer
Avoid hats, thick blankets, or overheating sleepwear, especially in the crib. Your baby’s head is their natural heat vent—covering it can lead to overheating.
🌡️ Ideal Nursery Temperature
Experts recommend keeping the nursery between 68°F and 72°F (20°C to 22°C) for safe sleep. A simple room thermometer (many baby monitors include this) can help you stay in that sweet spot.
I personally love using this room thermometer. It’s affordable and portable.
💤 Best Sleepwear for Every Season
Winter:
Summer:
Lightweight cotton onesie or short-sleeved romper
Muslin swaddle or light sleep sack
No socks or hats in warm rooms
Transitional Seasons:
Layers that are easy to remove
Dress baby according to actual room temp—not the calendar
💬 Final Thoughts from a Newborn Care Pro
You don’t need to obsess over the thermostat, but paying attention to your baby’s cues (and their chest, not their hands!) goes a long way in helping them sleep safely and comfortably.
Over time, you’ll learn what your baby prefers and feel more confident in how to dress them for sleep. And when in doubt? Lighter is safer than heavier. It’s easier to warm a slightly chilly baby than to cool down an overheated one.
Still unsure what sleepwear or sleep sack to use? Hop onto my calendar for an Ask-Me-Anything call!