The short answer
Sleep specialists such as the Sleep Foundation suggest a bedroom temperature of about 16°C to 19°C (60°F to 67°F). Treat it as a starting point. If you wake up cold or sweaty, move the temperature up or down by a degree or two until you sleep well.
Why a cooler room helps
Your body temperature drops a little as you fall asleep and through the night. A very warm bedroom can make it harder to fall asleep and easier to wake up. Many people sleep better when the room is on the cool side, with enough blankets to stay comfortable.
If your bedroom cannot get that cool
In a hot climate or in summer, 16°C to 19°C may not be possible. Do not worry about hitting the number. Get the room as cool as is comfortable for you. If your bedroom stays hot into the night, why a room gets hotter than outside explains why.
- Close the curtains in the daytime so the sun does not heat the room.
- Run the AC for a while before bed, then use a timer or a higher setting for the night.
- Use light cotton sheets and skip the heavy blanket.
- Use a fan to move the air. It will not lower the temperature, but it can help you feel cooler.
- Open a window only if the air outside is cooler than the room.
In winter
You do not need to heat the bedroom to daytime temperatures. A cooler room with warm bedding is usually fine. Do not let it get uncomfortably cold, and keep it warmer if you are older or unwell. Babies have their own advice: see the best room temperature for babies.
Humidity matters too
Damp air feels warmer and stickier. A bedroom at a normal temperature can still feel stuffy if the air is humid.
Check your bedroom temperature
A thermometer by the bed is the most reliable way to know. For other ideas on what feels right, read what is a comfortable room temperature.