For most adults, the ideal bedroom temperature is between 16 and 18°C. Around 18°C is a comfortable starting point for many people. That sounds cooler than what feels comfortable during the day, but that fresher temperature is exactly what helps your body switch off. If you tend to get hot at night, you will often sleep better at the lower end of that range. If you get cold easily, one degree higher may feel better, as long as the room does not become stuffy.
Why a cooler room often helps you sleep better
As you fall asleep, your body temperature naturally drops a little. A cool bedroom supports that process. It helps you feel sleepy faster and makes it less likely that you will wake up because of heat, sweating or a clammy feeling in bed. So you do not need to make your bedroom cold, just cool enough to relax comfortably.
If your bedroom is too warm
At 19 or 20 degrees, things do not have to go wrong straight away, but for many people that is already on the warm side. Your body gets rid of heat less easily, so you spend longer tossing and turning, sweat more quickly and sleep more lightly. Especially in summer, or with warm bedding, your bed can quickly start to feel stuffy. For practical tips: Sleeping cool in summer.
If your bedroom is too cold
Sleeping too cold is not pleasant either. If your feet are freezing or there is a draught blowing past your bed, you stay tense instead of relaxed. Below about 12°C, your body has to work harder to stay warm. That makes comfortable, deep sleep harder for most people.
Temperature guide: what usually feels comfortable?
Not sure whether your bedroom is about right? This quick overview will help.
| Temperature | Often feels like | Practical guide |
|---|---|---|
| 10-12°C | Chilly | Usually too cold for comfortable sleep |
| 15°C | Cool | Can work with a good duvet and no draughts |
| 16-18°C | Fresh and restful | Ideal for most adults |
| 19-20°C | Warm | Often a little too warm for restless sleepers |
How to get your bedroom to the right temperature more easily
With a few simple adjustments, your bedroom will often start to feel more comfortable quite quickly.
Without air conditioning
- Measure the temperature with a simple room thermometer instead of relying on feel alone.
- Turn the heating down an hour before bedtime.
- Air out the room briefly before going to sleep and keep strong sunlight out during the day with curtains or blinds.
- Avoid draughts, but do not seal the room off completely either.
- Work with layers and choose temperature-regulating bedding if you tend to sleep hot or clammy.
Sleeping with air conditioning
If your bedroom is hard to keep cool in summer, air conditioning is a practical solution, just like sleeping with a fan: pros and cons. Do not let the airflow blow directly onto your body and do not set the temperature ice cold. Often, pre-cooling or a quiet night mode is already enough to make the room feel fresher and drier. That way, you avoid lying awake because of the heat without making the room unpleasantly cold.
Useful settings for the night
- Aim for about 16-18°C.
- Use a timer or sleep mode.
- Keep filters clean for a fresh airflow.
Do not forget your bed either. The thermostat is only one part of your sleep environment. A lighter duvet and breathable summer bedding can do a lot to reduce that stuffy, clammy feeling that causes restless nights.
Frequently asked questions about bedroom temperature
Is 15 degrees in the bedroom too cold?
Not always. 15°C is cool for many people, but it can work perfectly well, especially in winter with a suitable duvet and no draughts. If your feet are cold, you pull every layer tightly around you or you wake up feeling tense, then it is probably just a little too cold for you.
Is 20 degrees too warm to sleep?
For many people, yes. 20°C is not extremely warm, but it is often just warm enough to make sleep more restless, especially if you sweat easily. If you spend a long time tossing and turning or wake up clammy, try lowering it by 1 or 2 degrees. See also: How to stop night sweats.
Which temperature is too cold to sleep in?
For most adults, below about 12°C becomes too cold for relaxed sleep. Your body then has to put in more effort to stay warm, and you often notice that in cold hands, cold feet and lighter sleep.
Is 10 degrees too cold for a bedroom?
Yes, usually. 10°C quickly feels chilly, especially if there is also damp or draught in the room. Only with lots of layers can you still make it bearable, but it is not comfortable for most people.
Does the window need to be open to sleep well?
Not necessarily. Fresh air helps, but an open window is not essential. More important is that the room is well ventilated without a cold airflow along your face or feet. In winter, airing the room briefly before bed is often more pleasant than leaving the window open all night.
Does different bedding help if you get hot quickly?
Often, yes. Breathable, moisture-regulating summer bedding feels less stuffy and helps release heat more effectively. That means a bedroom at 17 or 18 degrees can genuinely feel fresh and comfortable, rather than clammy or heavy.
