We are mom-supported. When you buy through links on our site, we may earn a commission.

How Dark Should Baby’s Room Be at Night?


A cot in a dark bedroom
How dark should the nursery be?

We have all been told or read that your baby’s bedroom should be dark, but is that just based on our understanding of adult sleep?
A baby’s needs are very different from our own, so we shouldn’t just assume they sleep better in the dark.

Will my baby actually sleep longer at night in a dark room or will he become scared and wake up?

Does darkness help my baby to fall asleep, or is it just more stressful for her?

We set out to do our own research, find the facts and give them to you.

Early Sunrise

We live in Sweden and the summers up here are very bright. In June it is not dark until after 11 and the sun rises again around 3 in the morning.

Our 17-month-old daughter has always slept in a bedroom with black-out roller blinds but the light seeped through. We noticed that as the nights got shorter and shorter so did Molly’s night sleep. Earlier in the spring, when the nights were still dark, she would typically go to bed around 7 or 8 and then wake up 11-12 hours later.

With the arrival of the short summer nights, we struggled to get her to go to sleep before 9 and she often woke up at 5. Something had to be done quickly.

We ended up hanging blankets and towels around the roller blind to stop any light from getting into the nursery.

The bedroom went from bright to dark and it made a big difference.

Getting her to go to sleep early is still hard but she is now back to sleeping 12 hours and she often wakes up after 9 in the morning. I can’t remember the last time we were able to sleep in like that but they are now quite common.

The darkness of the room is obviously important for Molly’s sleep and I would say it added about 2-3 hours of sleep to her night. I thought it would be very interesting to see how important darkness is to other babies so I put together a survey.

We asked 968 moms and dads how dark they keep their babies’ bedrooms and how quickly their babies go to sleep. We also asked for how long they sleep during the night.

A group of 968 people.
968 mums and dads took part in the survey.

Baby Sleep Quality in Light and Dark Rooms

The babies of parents in the survey were between 0-24 months old and we split them up into three age groups.

Of the 968 babies, 52% sleep in a dark room and 48% sleep in a bright room.

0-24 months

babies sleep (0-24 months)

0-6 months

babies sleep (0-6 months)

7-12 months

babies sleep (7-12 months)

13-24 months

babies sleep (13-24 months)

Does a Dark Room make your Baby Fall Asleep Quicker?

For 0-6-month-olds sleeping in a dark room, 74% would fall asleep quickly (within 20 minutes). Of the babies sleeping in a light room, 67% fell asleep quickly.

The numbers are similar for 7-12-month-olds. 74% fell asleep quickly in a dark room and 64% in a bright room.

For older babies, 13-24 months, darkness plays a bigger role. 78% of the babies who slept in a dark room benefitted and fell asleep quickly, whereas only 59% of those in light rooms managed to fall asleep quickly.

0-6 months

babies fall asleep (0-6 months)

7-12 months

babies fall asleep (7-12 months)

13-24 months

babies fall asleep (13-24 months)
The next graph shows the average time to fall asleep compared to the darkness of the room.

You can clearly see that the darker the room, the quicker the babies fall asleep.

Just like in the previous diagram, a dark room makes a bigger difference to the older babies than to the really young ones.

Average time to fall asleep in dark vs light rooms

average time to fall asleep

Will my Baby Sleep for Longer in a Dark Room?

So to the big question: Will my baby sleep longer in a dark room?

The answer: It depends.

In this diagram, you can see that for the 0-6 month-olds the average nights’ sleep does not get any longer in a dark room. So why is this?

Babies are not born with a circadian rhythm, and by this I mean their brains are not mature enough to distinguish between night and day. It takes between 2-4 months to develop a circadian rhythm, so we really can’t expect babies of this age to react differently in dark or light rooms.

Older babies, however, sleep for much longer if the room is kept dark.

On average, 7-12-month-olds get 19 minutes additional sleep, and 13-24-month-olds 36 minutes additional.

 

Additional minutes of sleep in a dark room vs a bright.

extra minutes sleep

Summary

The survey clearly shows that there are big benefits to having your baby sleep in a dark room.  In the 13-24 month category, babies who slept in a dark room got, on average, 36 minutes extra sleep per night.

Imagine how good you and your baby would feel with 36 extra minutes sleep in the morning? 36 minutes per night adds up to more than 4 hours per week!

So what about babies in the 0-6 month group? The survey shows that the night sleep will be the same length, so is there a point of making the room dark?

As I see it, there are two excellent reasons to let your young baby sleep in the dark:

  • The survey shows that your little one will go to sleep quicker the darker the room.
  •  As your baby grows older and develops, the darkness becomes more and more important. It is a good idea to make sure your little one is used to sleeping in the dark early on.

How to Make Baby’s Room Darker

The most important step to take is to stop sunlight, moonlight or street lights from streaming through.

There are permanent fixes such as taping privacy film onto the window but, I don’t recommend this. You want to have the ability to easily let the sunlight back into the room in the morning when it is time for your baby to be awake. The light during the day is as important as the darkness is during the night.

Instead, I suggest a two-step approach. A good black-out roller blind in combination with lined black out curtains that completely cover the top and sides of the window to stop that light sneaking in.

A window with a roll down blind as well as curtains.
Combine lined curtains with a roll down black out blind. Make sure the curtains overlap well.

Make sure no screens (iPad, Tv or computer), shine in the room. They give off a bright blue light and it is this type of light that have the biggest impact on the sleep cycle.

You will probably need a night light to check on your baby. Make sure this is dim and has a warm or red glow.

Conclusion

We have now seen how effective a dark room is for ensuring a good night’s sleep. I think most of us already thought this was the case, but these are the hard facts and evidence.

Making sure your baby’s bedroom is dark is such an easy and important step to take. It really surprised me when the survey showed that only about half of parents provide a dark bedroom for their little ones.

Don’t be one of the 48%. Come join the dark side!

Experienced Mommy
Experienced Mommy
Blessed mother of two boys and two girls, changing diapers and homeschooling for 20 years and counting. I love to research (I'm a CPA). And I really love to help other moms make wise and thoughtful decisions for their families.