A quiet moonlit bedroom for trying white, pink and brown noise: sheer curtains, a full moon over the water, and a lamp glowing beside a bed with a knitted throw

What's the difference between white, pink and brown noise?

White, pink and brown noise are all a steady shush, but they lean toward different pitches. White is a bright hiss, pink sounds like steady rain, and brown is a deep, low rumble. None of them has been proven best for sleep, so pink is a sensible first try, and your own ears decide the rest.

Noise is lots of sound frequencies playing at once, from low rumbles to high hisses, jumbled together at random. Its colour tells you how the loudness is spread from bass to treble.

The names borrow from light. White light holds every colour equally, so white noise holds every frequency equally. The other colours tip that balance toward the low end.

White noise: the hiss

White noise has the same energy at every frequency. That sounds balanced, but it isn't to our ears. Each step up in pitch (each octave) holds twice as many frequencies as the one below it, so most of the energy piles up at the high end. It comes out bright and hissy, like an untuned radio or a fan on full blast.

Pink noise: the rainfall

Pink noise turns the treble down gently as the pitch rises, so every octave gets the same share of energy. Most people hear that as more even and natural. They often compare it to steady rain, wind in the leaves, or a waterfall a short walk away.

Brown noise: the rumble

Brown noise turns the treble down even more steeply. It's named after the botanist Robert Brown and the random "Brownian" motion he described, not after the colour, and some people call it red noise. What's left is a soft, deep rumble, like heavy surf heard from indoors, a strong wind, or the low hum inside a plane.

An easy way to remember them: white is a hiss, pink is a rainfall, brown is a rumble.

Three colours, side by side

The squiggle is a short slice of each sound. The bars show how much energy sits in each step up in pitch, from low to high.

A simple picture, not a lab measurement. White leans toward the treble, pink stays even across the octaves, and brown leans toward the bass.

Why does a steady sound help at night?

Mostly, it's masking. What breaks sleep is often not how loud a sound is but how suddenly it changes: a door closing, a car going past, a voice after a long silence. A steady sound lifts the quiet floor of your room, so those sudden changes don't jump out as much. Your brain is brilliant at spotting differences, and a constant shush makes them smaller.

There's a gentler reason too. A sound you play every night can become part of winding down, a signal that the day is over, the same way a certain lamp or a favourite blanket can. If you'd like to build that kind of signal on purpose, our bedtime routine for adults shows how to put one together.

What does the research actually say?

Honestly, the science is still small and mixed. Some studies found steady sound helped people settle in noisy places, like hospital wards or busy streets. Pink noise got extra attention after lab experiments that played short, carefully timed bursts of it during deep sleep. That's a very different thing from leaving a speaker on all night, and those results aren't settled.

When researchers have pulled the noise and sleep studies together, they've generally judged the evidence limited and of mixed quality. Some people sleep better with noise and some notice no difference at all. A few sleep worse.

So nobody can say one colour is best for everyone. The most useful answer is a personal one: the best noise is the one you stop noticing, played as softly as still does the job.

Which one should you try?

If the sounds that bother you are high pitched, like voices through a wall or a whining appliance, white noise is worth a go, especially if you already love the crisp sound of a fan. Plenty of people find it too sharp for a whole night, though, so keep it low.

Not sure where to start? Try pink. It's the one most people describe as "like rain", and it sits comfortably in the middle.

Brown noise is the one to reach for when low sounds are the trouble, like traffic rumble or a neighbour's music, or when hiss just feels harsh. It's deep and cocooning. If it starts to feel heavy, a bit like pressure in your ears, switch to pink.

A quick guide, drawn from the notes above. Your own ears get the final say.
WhitePinkBrown
Sounds likeA hiss, a fast fanSteady rainA deep rumble
High sounds bother you, like voices
Low sounds bother you, like traffic
Good first choice if not sure
Watch forCan feel sharp, so keep it lowA gentle middle groundIf it feels heavy, switch to pink

Give each one a fair turn. Listen for a few minutes at a low volume and see whether it slips into the background. If you forget it's playing, that's a good sign. Then stay with it for a few nights, because any new sound takes a little getting used to.

How loud should it be, and where should it go?

Softer than you'd think. Aim for something quieter than a normal conversation: if you'd have to raise your voice to talk over it, it's too loud. Put the speaker or phone across the room, or at least away from your pillow. Headphones sit much closer to your ears, so keep the volume especially low if you use them.

If you only need help drifting off, a timer that fades the sound out means you aren't listening to it all night. We weigh up both options in sleep sounds all night or on a timer.

Whatever you choose, make sure you can still hear an alarm, a smoke detector or a child calling. And never use sleep sounds while driving.

Try all three side by side

You can hear them right now on our free noise player. It makes white, pink and brown noise live in your browser, with a volume slider and a sleep timer that fades out. Give each one a minute and notice which your ears settle into.

If you'd rather have a little texture than pure noise, rain or running water may suit you better. Our guide to rain sounds for sleep helps you pick the right kind, and sounds to help you fall asleep covers streams, fire, hums and stories too.

Still torn between the three, or wondering if rain or a story would suit you better? Take the quick sleep sound quiz.

This guide is general information, not medical advice. If poor sleep is affecting your days, please talk to a doctor.

Prefer rain and water to pure noise?

MoonEase has rain, stream, fireside and city sounds, bedtime stories, and a sleep timer that fades out gently. Six of the sounds are free and work offline.

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