Best Sounds for Sleep

Brown noise is the best noise to fall asleep to when a truck, a boiler or bass through the wall is what wakes you, because a deep rumble is the only thing that covers a deep rumble. Rain or pink noise is the better pick when the trouble is a TV, voices in the hallway or a few small sounds you cannot predict. Press play on both at a quiet setting and keep the one you stop hearing first.

Slo plays all of them free in this browser, with a volume you set yourself and a sleep timer, and no account to make. That test takes about a minute. Everything below is the same decision in more detail: what each sound is good at, how loud to set it, and whether to leave it running.

Which noise is best for sleep?

Match the sound to the thing that keeps waking you. Deep sounds need a deep sound over them; voices and clatter need a hiss.

Sound	What it sounds like	Best when	Listen
Brown noise	A deep rumble, like a waterfall a long way off	Traffic, a boiler or bass through the wall	Brown noise
Heavy rain	A broad hiss with small changes in it	A TV, voices or several small sounds at once	Rain
Pink noise	Rain heard through a wall, soft and even	You want one plain sound and no decisions	Pink noise
White noise	Bright static, close to an untuned radio	Sharp sounds: keys, doors, a voice next door	White noise
Fan sound	A mechanical wash with a faint motor hum	You grew up sleeping with a fan running	Ceiling fan
Ocean waves	Slow swells that rise and fall	An even wash feels cold to you	Ocean
Night crickets	A fine, repeating chirp with space around it	A silent room keeps you alert	Night crickets

What a sleep sound can and cannot do

Your hearing stays on all night. A car door, a voice on the stairs or the fridge kicking in stands out because it arrives into near silence, and it is the size of that jump your ear reacts to. If a quiet sound is already playing, the room is never fully silent. The same car door then stands out much less, so it’s less likely to wake you. That is all any of these sounds do, and it is enough to be worth trying.

Do not expect more than that from the research. Riedy and colleagues went through the studies on continuous sound as a sleep aid in 2021 and found the evidence weak and inconsistent, with a few studies pointing toward worse sleep rather than better. Pink noise gets sold as a deep-sleep booster on the back of lab work where short pulses were timed to a sleeper’s own brain waves, which is a different thing from a loop playing on a phone. And covering a noise is always second best to removing it, so fix the loose vent or the rattling window latch before you reach for volume.

1. Brown noise

Brown noise is a deep, soft rumble with hardly any hiss in it. Traffic, a boiler firing at two in the morning, plumbing, a neighbor’s bass: all of that is deep sound, and a rumble is what sits over it. It is the most played sound on this site, and the recording you get here is the deep brown one.

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A phone speaker cannot reproduce deep sound, so brown noise through one turns thin and slightly uneven. Earbuds you can lie on fix it, and so does a small speaker on the floor. If neither is an option, pink noise is the better use of a phone.

Level and timer: deep sound travels through walls and floors more easily than a hiss does, so a level that feels quiet to you may not feel quiet to whoever is on the other side of the wall. Leaving it on all night is reasonable when the road outside is busy all night. Play brown noise, or open brown noise for sleep, which is one layer at half volume with the timer set until morning.

2. Heavy rain

Rain is mostly hiss, and hiss is what softens a TV murmur, a door down the hall, footsteps and a faucet running somewhere in the building. It has small changes of its own, which is why people who find a flat sound unpleasant can usually live with rain. Heavy rain is the most played rain recording here.

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Pick the recording with care. Distinct drips, a gutter and rolling thunder are all events, and events are what you were trying to get rid of. A deep rumble also passes straight through rain, so rain alone will not do much about the truck outside.

Level and timer: rain covers things at a lower setting than white noise, so start lower than you think you need. Try rain, or rain sounds for sleeping, which puts a little brown noise under the rain and stops after 45 minutes. Our rain sounds for sleeping guide goes further into choosing between recordings.

3. Pink noise

Pink noise sounds like rain heard through a wall: full, even, and nothing in particular. It sits between a hiss and a rumble, which makes it the safe first test when you have no idea what you want and no interest in developing an opinion.

Pink NoiseReady to playLoadingNow playingCould not play this sound.

It is also the option that survives a bad speaker. Nothing in it depends on deep sound, so a laptop or a phone plays it more or less as recorded.

Level and timer: begin at roughly a third of the volume you would use for music and raise it only until the disturbance stops standing out. A 60 minute timer suits a street that goes quiet after midnight. Play pink noise on its own, or open pink noise for sleep, which runs one layer at half volume until morning.

4. White noise

White noise is a bright, even hiss, close to an untuned radio. That brightness is why it blurs voices through a wall, keys on a hook and an elevator door better than a rumble does, and it is also why people call it harsh at bedtime. At the same setting it sounds louder than brown noise, and some listeners find it tiring after an hour.

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If it sounds fatiguing, you are hearing the hiss, and pink noise is the same idea with the brightness pulled back. Reach for white noise for sleeping when the sounds getting to you are genuinely sharp, and read why white noise helps sleep for what the studies do and do not show.

5. Fan or air-conditioner sound

A fan is the oldest sleep sound in the house, and familiarity does real work here: a sound you have heard since childhood is easy to stop noticing. What you get depends on the machine, though. A ceiling fan is broad and airy, while an air conditioner hums lower and steadier.

Ceiling FanReady to playLoadingNow playingCould not play this sound.

A recorded fan often beats a real one, because a recording cannot rattle, change speed or shut off at three in the morning. Play ceiling fan or the fan noise sleep preset, which sets a ceiling fan over quiet brown noise. Our fan sounds for sleep guide compares the machines, and answers whether a fan counts as white noise.

6. Ocean waves

Surf moves slowly and you can more or less tell what is coming, which suits people who find an even wash cold. Each swell is still an event, so watch for the moment the rhythm becomes something you are waiting for. That is attention, not rest.

Ocean WavesReady to playLoadingNow playingCould not play this sound.

Level and timer: the quiet gaps between waves are where outside noise gets back in. A steady sound underneath fills those gaps, which is what ocean sounds for sleeping does with quiet pink noise behind the waves, running until morning. Plain ocean waves are fine in a room that is already fairly quiet. Our ocean sounds for sleep guide has more on picking a recording.

7. Night crickets or a quiet forest

Some people cannot sleep in a silent room and lie there listening to the silence. Something present but undemanding works better for them than nothing, and night crickets fit that: a fine chirp with plenty of space around it. Crickets over a quiet brown rumble is a common pairing, since the crickets give the room a bit of life and the rumble covers the traffic they cannot.

Night CricketsReady to playLoadingNow playingCould not play this sound.

Level and timer: keep nature recordings restrained. Birds close to the microphone and branches cracking are alerts in disguise, and a cinematic forest is far too busy for a bedroom.

What type of noise is best for sleep?

Brown and pink are the colors most people settle on for bedtime, because both sound softer than white at the same setting. White covers voices and sharp sounds better, and it is also the one listeners most often complain about.

Here is what each one is like in a bedroom:

• Brown noise is a deep rumble. Best against traffic, plumbing or a boiler.
• Pink noise sits between a hiss and a rumble, close to rain behind a wall. The safe middle pick.
• White noise is a bright hiss. Best against sharp sounds, speech through a wall in particular.
• Green noise has no agreed definition, so what you get depends on who made the recording.

None of these has been shown to change the shape of your night. Choose by the disturbance you are covering and by what you can stand listening to. Our guide to noise colors covers the rest of the set, including grey, blue and violet.

Is sleep music better than noise?

Music is the better choice before bed, and steady sound is the better choice once the light is off. A melody gives your mind something to follow. You know roughly where the tune is going, and part of you stays awake to hear it get there. Steady sound has nowhere to go, which is the point of it. Words make this worse, because your brain keeps trying to make sense of them whether you want it to or not.

So use both, at different times. A quiet album while you brush your teeth and get into bed, then a rumble or rain for the night. If you would rather have something with a bit of life in it than a plain wash, the sounds people usually call relaxing are the slow ones with no speech: rain on a window, distant surf, crickets, a fire dying down.

Choose by what keeps you awake

Traffic, a boiler, a neighbor’s bass. These are deep-sound problems, so use brown noise. A brighter hiss would have to be much louder to cover the same rumble, and at that volume it becomes the problem.

A partner snoring. Snoring is the hardest case here: it covers a wide range of pitches and it comes in bursts. A broad, steady sound such as rain or pink noise covers more of it than a narrow one, and earplugs under the sound do more than any amount of volume. We go through the whole setup in sleeping with a snoring partner.

Thin walls and voices. No sound removes speech, because the brain listens for it; all you can do is blur the words enough that they stop being words. Pink noise is usually the best compromise, and white noise if you can still make out what is being said.

A room that feels too quiet. Anything gentle and continuous will do. A fan, light rain or crickets, set near the point where you can only just hear it.

Racing thoughts. Sound will not switch your head off, and it is worth knowing that before you try. Some people do find that a steady background gives their attention somewhere harmless to sit, which is a modest thing and sometimes enough. If falling asleep is hard most nights, that deserves proper attention: cognitive behavioral therapy for insomnia has much stronger clinical support than any sound, and a doctor can point you to it.

How loud, and does it run all night?

Use the quietest level that makes the disturbance stop standing out. That is lower than most people pick. The test takes a second: if you can still clearly hear the thing you are covering, nudge it up; if you are aware of the sound you added, bring it down. Louder is not better, and a percentage on a phone tells you nothing about how loud the room is, since that depends on the speaker and how far away it sits.

You are probably reading this in bed, so the cheap answer is earbuds you can lie on. A small speaker across the room or on the floor works too. Keep it off the pillow and keep your alarm audible, along with anyone who might need you in the night. The NIDCD notes that sound at or below 70 dBA is unlikely to damage hearing even over long stretches, while long or repeated exposure at 85 dBA and above can. A bedtime background sits well under both.

Whether to use a timer or play it all night depends on when the noise outside happens. When the street settles after midnight, 30 or 60 minutes is plenty and the room goes quiet along with you. When the disturbance runs until morning, like a highway or a snorer, a quiet sound that runs until morning makes more sense, because a sound cutting out at two can wake you the way any other event does. Every sleep page here has an all-night option, and a fade-out beats an abrupt stop.

Every so often, run a night with nothing playing. Sleep sounds are easy to keep out of habit long after they stopped earning their place.

A three-night test

Give one sound three nights before you judge it, and note the same things each morning.

1. Night one. Set the sound at the lowest level that makes the disturbance recede. Note how often you remember waking, and whether the sound itself pulled at you.
2. Night two. Same sound, same level. Hold everything else you control steady: same bedtime, same window.
3. Night three. Same again, and this time note how you feel getting up, not only what you remember of the night.
4. Night four, no sound. Run the room with nothing playing, so you have something to compare against.

Keep the sound if those nights were calmer and it never became the thing you noticed. After that, change one thing at a time: level first, then the sound, then whether it runs all night. If your problem is waking in the second half of the night rather than getting to sleep, our guide to sounds for deep sleep covers that case.

Bedtime presets

Two starting mixes for winding down

Each one opens in the mixer with a volume already set for every sound in it. Press play, then lower or remove anything that pulls your attention, and keep the quietest version that still works.

Rainy Cabin at Bedtime

Gentle rain and a mild wind, with one owl a long way off over soft pink noise.

• Pink Noise 48%
• Gentle Rain 36%
• Mellow Wind 16%
• Owl 10%

Play this mix View details

Pink Noise and Fireplace for Winding Down

Soft pink noise with a fire crackling in it, for the last hour before bed.

• Pink Noise 56%
• Fireplace 35%

Play this mix View details

Frequently asked questions

What is the best noise to fall asleep to?

Start with brown noise if a truck, a boiler or bass through the wall is what wakes you, because a deep rumble covers a deep rumble. Start with rain or pink noise if the trouble is a TV, voices in the hallway or a handful of small sounds you cannot predict. Both take about a minute to judge, and the one you stop hearing first is the one to keep.

Is white, pink, or brown noise better for sleep?

Brown noise is a deep rumble and the easiest to leave on at a quiet setting. Pink noise is gentler than white and sounds a lot like rain behind a wall. White noise is a bright hiss that blurs voices and sharp sounds better than brown does, though it sounds louder than brown at the same setting and some people find it tiring. Pick by the noise you are covering, not by which color sounds most impressive.

What are the most relaxing sounds for sleep?

The sounds people call relaxing at bedtime move slowly, carry no speech, and hold nothing you want to wait for: rain, a fan, distant surf, crickets in the background. A sound is working when you forget it is on. If you notice yourself following a drip or counting waves, switch to something plainer.

Is sleep music or steady noise better at bedtime?

Music is better at settling you down before bed, and steady sound is better once the light is off. A melody has a shape you can follow, and following it keeps part of you awake. A common compromise is a quiet album while you get ready, then a plain rumble or rain for the night.

Is it okay to run brown noise all night?

Running it all night makes sense when the noise you are covering also lasts all night, like a main road or a snoring partner. Keep the level quiet, keep your alarm audible, and keep the speaker off the bed and away from your head. When only the first half hour is a problem, a 30 or 60 minute timer does the job and the room goes quiet with you.

Does 432 Hz help you sleep?

No review of the research and no clinical guideline backs the claims made for 432 Hz or the other solfeggio tones. Pitch measured in hertz is a modern convention, so the ancient origin story does not hold up either. Play the tone if you like how it sounds, and expect nothing from it that any pleasant sound would not give you.

What is the best sound frequency to fall asleep to?

There is no established sleep frequency. A single tone leaves almost everything in the room uncovered, so a rumble, a hiss or rain is the practical choice when traffic, voices or a fridge keeps cutting through.

Research referenced

• Riedy and colleagues (2021), Noise as a sleep aid: A systematic review.
• Ngo and colleagues (2013), Auditory Closed-Loop Stimulation of the Sleep Slow Oscillation Enhances Memory.
• Henin and colleagues (2019), Closed-Loop Acoustic Stimulation Enhances Sleep Oscillations But Not Memory Performance.
• World Health Organization (2018), Environmental Noise Guidelines for the European Region.
• National Institute on Deafness and Other Communication Disorders, Noise-Induced Hearing Loss.
• National Center for Complementary and Integrative Health, Sleep Disorders and Complementary Health Approaches.

Sound is not a treatment for insomnia, sleep apnea or any other sleep disorder. Seek qualified care when sleep problems continue, affect your days, or involve loud snoring and pauses in breathing.

Related guides

• 6 Best Sounds for Deep Sleep
• Rain Sounds for Sleeping
• Fan Sounds for Sleep
• Ocean Sounds for Sleep
• A Guide to Noise Colors
• Why White Noise Helps Sleep

Filip Kowalski is the developer of Slo and writes about sound, sleep, and focus.