Quick answer
As dark as practical, without making the room unsafe
- The goal
- Reduce light reaching your eyes, not necessarily to pitch black.
- Biggest culprits
- Standby LEDs, phone screens, street light and a bright hallway.
- If you need light
- Use a low, warm, downward-facing source you can reach from bed.
- Remember
- Morning light is the other half — you want it bright when you wake.
Why night-time light matters
Your body clock is set mainly by light and dark. Bright light in the evening and through the night can push your internal timing later and make it harder to feel sleepy, while a dark room supports the wind-down. This is why the same bedroom should be dark at night and bright in the morning.
It is easy to fixate on curtains while ignoring smaller sources that sit much closer to your eyes. A standby LED a metre from your head can matter more than a faint glow at the window, because intensity falls off quickly with distance.
Distance beats brightness
A dim light close to your face can reach your eyes with more intensity than a brighter one across the room. Deal with nearby sources first.
A two-minute light audit
Stand in the doorway with the room lights off and look at what is actually glowing. Most bedrooms leak light from a handful of predictable places:
| Source | Typical fix |
|---|---|
| Standby LEDs on TV, charger and router | Cover with tape or a sticker; move chargers out of the room |
| Phone or tablet on the nightstand | Face down, face away, or leave it outside the bedroom |
| Street or security light through the window | Better covering; see darkening a room |
| Light under the door from a hallway | A draught excluder strip, or dim the hallway |
| Bright clock or smoke-alarm LED | Choose a dimmable or red display; reposition sensors |
| Moonlight and early dawn | Close curtains or add a lining |
Often the fix is not a new purchase at all, but moving a charger, turning a screen over, or re-aiming a night light.
Fixing the sources you control
- Start with the closest source. Anything within a metre or two of the pillow first.
- Remove light, do not just dim it. Tape over small LEDs; unplug or relocate glowing devices.
- Deal with the doorway. If light spills from a landing or bathroom, a simple draught excluder on the bedroom door can help.
- Then the window. Once the small sources are gone, a proper window covering handles the rest — sizing matters more than fabric here.
- Check appliances you cannot move. A router or alarm that must stay can often have its light taped or faced away.
Two caution points. Some people need a little light for safety or for getting up at night — total darkness is a goal, not a rule. And a fully sealed, unventilated room can trap moisture, so cover light without sealing away the air.
If you do need some light
Not everyone wants or can manage a pitch-dark room. If you need light for safety, for children, or for night feeds, the aim changes from "none" to "as little, as warm, and as low as possible":
- Use a low, warm light. A dim, amber-toned night light is less disruptive than a bright white one.
- Keep it below the bed or angled down. Light should reach the floor, not your eyes.
- Choose motion- or manually triggered rather than always-on, so the room stays dark unless you need it.
- Put the switch within reach so you are not reaching into the dark and knocking things over.
Over the long run, a cool, very dim glow is a reasonable compromise for anyone who needs some visibility — and it is far better than leaving a bright phone face-up on the nightstand.
Frequently asked questions
Does a night light stop you sleeping?
A bright, cool night light close to the eyes can be disruptive. A dim, warm, downward-facing one is a much smaller compromise if you need some visibility.
Do I need total darkness?
Not necessarily. The aim is to reduce light reaching your eyes as much as practical. Few bedrooms are ever truly pitch black, and that is fine.
Is red light better at night?
Warm, low-intensity light is generally preferred at night over bright white light. Whatever the colour, keeping it dim, low and far from your eyes matters most.
Should I cover my smoke alarm LED?
Do not cover alarms or safety equipment. If a bright indicator bothers you, reposition it or choose a model with a dimmer indicator when it is due for replacement.
Sources and research notes
This guide is about the bedroom environment, not the treatment of sleep problems. Guidance reflects general sleep-environment advice on light exposure.
Written and edited by the Resthearth Editorial. Each guide starts from a real bedroom decision, is checked against the sources listed above, and is updated when guidance changes. We are an independent editorial desk, not medical professionals — read how we research and update our guides.
