The definitive guide to white noise and sleep

Some people are lucky, they can sleep through a tornado, but most of us struggle to fall asleep in a noisy environment. So what do you do if your neighbour’s dog insists on barking all night or traffic noise keeps you awake? If that’s the case you might want to consider trying out white noise.

What is white noise?

In simple terms, white noise is a special type of sound signal which is used to mask background sounds. When used to promote healthy sleep, white noise helps to drown out sounds which might otherwise prevent you from either falling asleep or waking up whilst asleep.

In technical terms white noise can be described as noise whose amplitude is constant throughout the audible frequency range.

White light
White noise, like white light, consists of all frequencies combined together

A useful analogy is that of white light, which as we all know from school, contains all the colours (frequencies) combined together.

White noise theory has it’s origins in mathematics and engineering and these days it has applications in fields as diverse as acoustics, electronics, computer programming and even economics.

If you want to delve deeper, Wikipedia which has an excellent resource on the science of white noise.

What does white noise sound like?

Click below to play a sample of white noise. CAUTION: Do not play loud if wearing headphones

Genuine white noise can only be generated electronically and sounds similar to TV or radio ‘static’. It is not very pleasant on the ears as it contains a lot of high frequency energy. 

Other types of ‘white noise’ sounds

Sometimes “white noise” is used as a general description for any type of constant, unchanging background noise. It’s become a colloquial term for a diverse range of sounds including:

  • nature sounds – rain, sea/waves, crickets chirping, jungle etc
  • machinery noises – air conditioning units, washing machine
  • ambient soundscapes – aircraft interior, crackling campfire, crowd noise
Some people prefer to listen to these types of sounds when they’re trying to get to sleep in preference to the harsh tone of pure white noise.

Incidentally, there are many other colours apart from white including red, violet, grey even brown noise. The different colours represent a specific spectral density and they have various applications in acoustics, engineering and physics. One such variant, pink noise, has been studied as a potential sleep aid with some promising results.

How does white noise work?

The idea of adding more noise in your bedroom to help you sleep may sound counter intuitive, but it works because white noise blends the external sounds (barking dog,traffic etc) into the overall background noise, so your brain pays less attention.

According to neuroscientist Seth S. Horowitz, our hearing has evolved as an alarm system, and it works even when we’re asleep. We become habituated to most background sounds unless they flag up on our cognitive radar as being worthy of attention.

It’s the context of the sound, not necessarily the volume that keeps us awake. That’s why it’s possible for some people to fall asleep in the middle of a noisy nightclub. In the same way, a distant barking dog can set off a startle response even when we’re unconscious and asleep.

What is noise masking?

When you add white noise (or a similar sound) to your sleeping environment, you’re utilising a principal known as sound masking. Rather than drowning out the offending sounds, they become ‘masked’ by the frequencies of the white noise signal. We can use light again as an analogy.

Imagine being in a dark room and you switch on a flashlight. You immediately notice the light source. But what if the room is already brightly lit? The flashlight is now barely noticeable because it has been “masked” by the brighter room lights.

Sound masking - an analogy with light
Sound masking – an analogy with light

As well as helping you get to sleep, sound masking is used extensively in offices to reduce the effect of distracting conversations and also in treating tinnitus, a hearing disorder that causes a constant ringing in the ears.

Music vs white noise

The sleep promoting qualities of music have been extensively studied, and indeed music has been shown to be effective in improving sleep quality. However, music doesn’t contain the wide range of frequencies that are needed to mask intrusive sounds, so it’s less effective than white noise in this respect.

Music can also stimulate emotional responses, memories and other associations which may prove counteract your sleep promoting efforts. Music is probably more suited for relaxation rather than as a means to ‘block out’ other sounds.

Babies, white noise and sleep

Baby sleep rhythms

Even before they’re born, babies are quite used to loud noises. The womb, is a surprisingly noisy environment. However, newborns also have an immature nervous system which makes them especially ‘jumpy’.

This is because we are all born with a pre-programmed ability to respond to loud, potentially threatening sounds or sudden movements. This ‘startle reflex‘ causes babies to instinctively flinch, clench their fists and in some instances start crying.

When you factor in a baby’s as yet untrained body clock, it’s no surprise that newborn sleep in the first few months is very often hard to come by.

Swaddling can help stifle the physical effects of the startle reflex, but if sleep problems persist, white noise might provide some help.

White noise is not unlike the instinctive ‘shhhush’-ing sound parents make when trying to comfort or quieten their child. Whilst not a cure-all, many parents have testified to the calming effect of baby sound machines and how they have helped in achieving sounder sleep for their newborn.

Is white noise harmful?

No long-term studies have been made on the effects that white noise has on humans and indeed much of the research in this field has so far produced positive results. One study looked at noise disturbances in intensive care units (ICU) and found that episodes of wakefulness were reduced when the ICU noise was mixed with white noise.

Another study, although unrelated to sleep, showed that white noise proved beneficial in improving concentration and cognitive performance in ADHD patients.

However, a 2014 study titled ‘Infant Sleep Machines and Hazardous Sound Pressure Levels‘ looked at the effect of sound machines on the health of sleeping infants. The study was only small but the main recommendation was that babies should not be exposed to white noise/sleep sound machines above a volume level of 85dB (equivalent to the noise of a hairdryer) for more than 8 hours.  (check out this link for apps that can measure sound levels easily) It also said that sound machines should be placed away from the crib, not next to your baby.

In related research a 2003 study found that “exposure to continuous, unpatterned sounds such as white noise delayed development of the brain’s hearing center in young rats.” An infant brain needs stimulation in order to develop properly and over reliance on white noise may limit the range of sounds the baby gets to hear.

So whilst there are some cautionary measures to take into account, there’s no clear evidence as yet to say that using a sound machine is definitely harmful for you or your newborn. The important things to remember are:

  • limit the volume of the sound machine to around 50dB
  • don’t place the sound machine next to the crib
  • use your sound machine sparingly and don’t keep it on all the time

More resources  here.

Best white noise sound machines of 2022

There are lots of ways to experience white noise sleep sounds that we’ll talk about later; you can listen to white noise on Youtube, download white noise apps, or even hack together your own DIY sound machine but  of the easiest ways to enjoy white noise is with a dedicated white noise machine (aka sound machine, sound conditioner). They are a great option for people who like simple, push button functionality and don’t want to tie up a CD player or computer for playback device.

Manufacturers choose not to use the term “white noise machine” as modern gadgets tend to offer a range of electronic and pre-recorded sounds for you to choose from. There’s a dizzying array of machines to choose from. Here are our recommendations for some of the best sleep sound machines in 2022

Marpac Dohm

This is the grand-daddy of white noise machines. The Marpac Dohm (formerly known as the Sleepmate/Sound Screen 980A) is a variant of a design that has been around for over 50 years. Marpac describe the Dohm as a ‘sound conditioner‘ rather than a white noise machine.

It uses a mechanical element rather than electronics – the noise is generated by a whirring internal fan. You can change the tone by adjusting air vents on the side. The Dohm has two settings, a slow and high speed which adjusts the volume and pitch of the fan sound accordingly.

Despite being relatively basic in its feature set, the Dohm is one of the most enduringly popular sleep sound machines of all time and has nearly 4000 reviews on Amazon. Users seem to love the simplicity of the design and Marpac have wisely chosen to keep the Dohm simple and uncomplicated

Check price at Amazon

LectroFan by Adaptive Sound Technologies (ASM)

Our second recommendation is the ‘Lectrofan frmo Adaptive Sound Technologies. ‘LectroFan uses patented technology to generate relaxing soundscapes on the fly, eliminating repetition by blending lengthy, naturally recorded, high-definition sounds together.

Their range of sleep sound machines include the  Sound+Sleep ( aka Ecotones ASM1002) and the Nomad. These devices also have an intelligent feature which automatically adjusts the volume in response to ambient sounds like coughing or snoring in the bedroom.

The LectroFan Micro is a tiny portable version of the larger device. With a built-in battery for up to 16 hours use, a Bluetooth speaker and the same high-quality sounds of its larger sibling, the ‘LectroFan Micro features a neat, twist action and, as its name suggests is tiny enough to fit in the smallest of travel bags for overnight trips or longer holidays.

Check price at Amazon

AuCuTee Q1 White Machine Machine

A new kid on the block, the AuCutee Q1 is a unique sleep sound machine that features individual sound mixing features. Boasting 10 high-quality non-looping nature and mechanical sleep sounds, each of which can be individually adjusted in level to create your own personal sound mix.

AuCuTee QS1 Sound Therapy Machine
AuCuTee Q1 features individual sliders for mixing your own sleep soundscape, plus a built in wireless Qi phone charger

For instance, you could create a backdrop of crashing waves with the sound of crackling camp fire. Or how about a soothing lullaby blended with some gentle birdsong? An adjustable sleep timer allows you to set the sound to switch off in 30, 60 or 90 minutes.

As well as the sound mixing features, the AuCuTee Q1 can be used a Bluetooth speaker to play your own music on. Plus, if that’s not enough, the top of the device has a built in wireless inductive phone charger. So no need to fumble for USB lead at night to charge your phone, simply place your iPhone or Android device on top of the Q1 before you go to sleep, and when you wake up it will be fully charged.

Check price at Amazon

Other sleep sound machines

HoMedics sound machines are part of its health and wellness range of products for sleep, relaxation and mediation.

Sound Oasis have been making a range of sleep sound therapy systems since 1993.  The Sound Oasis Sound Therapy System uses built in sounds such as ocean surf, stream, a rain noise generator as well as a traditional white noise setting.

Big Red Booster makes a range of  sound machines for those on a budget. Their most popular model, the BRRC107 costs only $20 has over 5000 reviews on Amazon and a 4-star rating.  You get 6 high quality sounds, a sleep timer and the option to power it with 3 AA batteries.

Nightingale Sleep System

If you want to experience the very latest in sound masking technology, then you need to check out the Nightingale Sleep System. A truly 21st century piece of sleep-tech, Nightingale uses advanced psychoacoustic technology to create a ‘sound-blanket’ in your bedroom, in effect enveloping you in relaxing sounds.

Designed by Cambridge Acoustics, world leaders in sound-masking technology for the corporate environment, Nightingale also offers a range of IoT (internet of things) functionality to integrate with smart home devices like Amazon Alexa, Nest and the ‘connect-anything’ software platform IFTTT.

Free white noise solutions

You don’t necessarily have to spend any money at all if you want to try white noise as a sleep solution. Here are some tips that won’t cost you a penny.

Use an old radio/boom-box – anything with an FM tuner should suffice. Just dial in between stations (or break the antenna) and you’ll have a perfectly good approximation of pink noise. We don’t recommend using TV as a source as the flickering light can have a detrimental effect on sleep quality

Use a fan – the whirr of a standard desk fan can be ideal for sound masking

Free white noise MP3s

there are loads of places you can get free white noise and nature sound MP3’s. You’ll still need something to play the MP3s back -but any computer or mobile phone should suffice. Here are a couple of Sleep Junkies recommendations for making your own sleep sound track:

  • – mix and download your own custom sleep sound track. Over 50 different source sounds including Pink noise, nature sounds animals and even Darth Vader.
  • – a huge open-source (free) sound library with over 1 million downloadable clips. Just use the search engine at the top of the page and type “white noise” (or whatever you like)

White noise on YouTube

what did we do before the days of YouTube? These days we can find anything on the world’s largest video jukebox. When it comes to white noise on Youtube you’re spoilt for choice – everything from nature, to air conditioners and even ambient sounds from inside a Starship (obviously not a real one). Check this link for 10 hours of white noise on Youtube.

White noise sleep apps

One of the easiest ways to ways to try white noise is with a smartphone. If you’ve already got an Android device or iPhone, there are countless free and paid apps designed to help improve your sleep.

The main advantage of using a white noise app is convenience. Many people already keep their phones by the bedside, so there’s no extra equipment to worry about.

One the negative side, some of the free apps use low quality sounds that might be more annoying than soothing. In addition, you’re not going to get the best sound quality with just your phone speaker. All this taken into account, white noise apps are a very popular way to get to sleep.

Here are a couple of the most popular cross platform white noise and sleep apps available for iOS, Android, Blackberry and Windows

Pzizz. Whilst not strictly a white-noise app, Pzizz has been making audio software for sleep and relaxation for over 20 years. Their patented technology has garnered lots of attention and high-profile fans including the late Steve Jobs. Check out our interview with Pzizz CEO Rockwell Shah

White Noise by TMSoft (free/premium). With a recommendation by the TV celeb Dr Oz this is currently the most popular white noise app on the market. There’s over 40 sounds to choose from plus you have the ability to create your own playlists by mixing sounds together.

Relax Melodies by Ipnos Soft (free/premium) You get over 88 high quality sounds plus 6 binaural beats to use for “brainwave entrainment”.


If you’re struggling with insomnia, anxiety or general restlessness at night and wondering how to fall asleep without resorting to pills or potions, there’s no excuse not to try out white noise or sleep sound therapy. It’s a simple, non-invasive treatment that doesn’t have to cost you a penny and if used correctly there are no known side-effects.

White noise for sleep is one of the best and most simple techniques you can use to improve your night’s rest. Give it a try and let us know in the comments!

21 thoughts on “The definitive guide to white noise and sleep”

  1. “Even before they’re born, babies are quite used to loud noises.” Not quite. Intrauterine hearing is by bone conduction, since the middle ear is filled with fluid. This results in severe attenuation of higher frequency sounds, up to 20-30dB. Exposing babies to high levels of high frequency sounds — and the hiss of white noise comes from its heavy high-frequency content — seems like a bad idea.


  2. Thank you, indeed, there is a distinction. The unborn baby’s acoustic environment has a completely different frequency spectrum (ie a lot of high frequency attenuation). However, the womb does not completely insulate the baby from external noise, hence, a pregnant woman at a rock concert, or standing at a busy road junction is exposing her unborn to considerable sound levels.

    The point I’m making in the article is that unborn babies are quite used to noise, and once born do not need to be in a ‘silent’ environment to fall asleep.

    Also I agree that “Exposing babies to high levels of high frequency sounds” is a bad idea. As I state in the article, babies have sensitive ears and white noise machines should be set to a volume level akin to light conversation.

  3. I live in a rural area where propane “crop cannons” are used to scare
    away birds and deer from farm fields. Unfortunately, those devices are
    only turned on at night. It is so frustrating trying to get to sleep
    when you randomly hear booming sounds, but the white noise machine I
    found at
    really helps me to not notice those booming noises so much so I can get
    to sleep.

  4. I play a white noise fan for babies tune on Spotify – this has become my no.1 tune! As soon as colic kicks in and the baby starts to shift his legs up an down to help digest his milk and he lets out a few screams, I turn on the fan noise on my little Soundwave (VERY affordable portable speaker: and the crying just stops, the baby immediately calms down and in 30min he shoots off to sleep. I keep the white noise tune going for another hour and we get at least 3 to 4 hours sleep out of the little one. He does feed well though. It also helps us adults sleep pretty deeply – amazing!

  5. I find white noise irritating and i cant sleep with it. What else
    can I do to block the sound outside?

  6. I find white noise irritating and i cant sleep with it. What else
    can I do to block the sound outside?

  7. White noise doesn’t help to ‘block’ out external sound – if you live somewhere really noisy, you might be better off with a pair of ear plugs to help you get to sleep.

    White noise is about masking sounds that occur on and off, like a barking dog etc. You don’t have to use the ‘hiss’ type of sound to achieve masking. On the White Noise iphone app, my favourite is the crackling campfire sound. Other people like waves crashing, rainfall – try out some different sounds and see how you get on.

  8. My absolute favorite white noise app is White Noise HD:

    It’s by far the best white noise app out there. We use it consistently during nap time on an old iphone hooked up to some speakers. It’s so simple to use and does’t have a million different settings or confusing options, unlike all the other one’s I’ve tried. Plus, it’s free! Hope you find it as useful as we have.

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  10. OUCH I just listened to that sample of white noise. Stressed me out and hurt my ears. No way I could fall sleep with THAT! That’s worse than the traffic

  11. Yes, it’s not very nice. I’ve added a cautionary note for people listening on headphones.

  12. Excellent article, tapped into most of the benefits and uses of white noise. I am currently researching the similar topics and have gained a comprehensive chunk of knowledge from here.

    For the guest commenter, who said that white noise has hurt his ears, I should say using white noise requires you to follow some rules.

    white noise should be played very loud
    white noise should be used to mask sounds not to mask your ears with the noise. So, you need to put the white noise source closer to the disturbing noise source and way from your ears.

    you can feel the difference after following some of these tips. hope my comment was helpful.

    thanks for sharing!

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  15. I’m curious about the Bose in-ear headphones for white noise, mainly how healthy it is to have sound on all night at a moderate volume level over a long period of time.

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