The “Magic” Number: 60°F to 65°F

For most healthy adults, the sweet spot for sleep lies between 60°F and 65°F (15.6°C to 18.3°C).

Why does this work?

Your body follows a circadian rhythm that naturally lowers your core temperature as evening approaches.¹ This “cooling down” process is a signal to your brain that it’s time to sleep.²

• The Cooling Process: To shed heat, your body expands blood vessels in your skin, often making your hands and feet feel warm as they release internal heat.
• Environment Connection: A cool room supports this natural dip in body temperature.³ If the room is too hot, your body struggles to reach its low-point temperature, leading to restless tossing and turning.

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Sleep Temperatures Across Life Stages

While the 60–65°F range is the standard, certain age groups have unique needs.

Infants (Birth to Toddler)

Babies cannot regulate their body temperature as efficiently as adults.⁴

• The Range: Aim for 60°F to 68°F (16°C to 20°C).
• The Safety Factor: Avoid overheating, as high temperatures are linked to an increased risk of SIDS.⁵
• The Check: Touch your baby’s chest or the back of their neck. If they are sweaty or hot to the touch, remove a layer. They should sleep in a breathable sleeper or sleep sack—never a hat indoors.

Older Adults

Recent research from 2023 suggests that as we age, our ideal temperature range climbs slightly higher.⁶

• The Range: 68°F to 77°F (20°C to 25°C).
• The Impact: Efficiency can drop by 5% to 10% when the room gets warmer than 30°C (86°F).

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Hot vs. Cold: Which is Worse?

Condition	Impact on Sleep
Too Hot	Significantly reduces REM (dreaming) and Slow Wave (deep) sleep. High humidity makes this even worse.
Too Cold	Generally less disruptive to sleep cycles than heat, but can make it physically difficult to fall asleep initially.

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Pro-Tips for Temperature Control

If you find yourself waking up throughout the night, try these temperature-regulating strategies:

• Programmable Thermostats: Set your HVAC system to automatically drop the temperature 30 minutes before you plan to head to bed.
• Seasonal Bedding Swaps: Use heavy down comforters for winter and switch to lightweight cotton or linen coverlets during the summer months.
• Air Circulation: Use a ceiling or box fan. This not only keeps the air moving but provides white noise that can mask disruptive outside sounds.
• Window Management: If you don’t have AC, open the windows during the evening to let in the cool night air, then close the curtains during the day to block out solar heat.

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The Takeaway

Your bedroom should feel like a cool “cave.” While most people thrive in the low 60s, pay attention to your own body. If you wake up with cold toes, add a blanket; if you wake up damp with sweat, it’s time to crank the fan or lower the thermostat.