Pink Noise
Short answer
Pink noise is a steady, even sound, like rain on a roof or wind in the trees. It is softer than white noise and lighter than brown noise, with deep and high sounds in balance. That makes it a good first choice if you are not sure which colour you want.
What Pink Noise Actually Sounds Like
Pink noise is the colour people describe without thinking of machines. Steady rain on a roof, wind in a tree in full leaf, waves a few hundred metres away, a shower running behind a closed door. White noise sounds electrical and brown noise sounds like the earth rumbling. Pink noise sounds like weather.
That is not a coincidence. Many natural sounds have a balance close to pink noise, and our ears seem to accept it as normal in a way they do not accept white noise. Whatever the reason, in blind tests listeners most often call pink noise natural. It is also the colour that people feel least strongly about, for or against.
It is also the most balanced of the five. You can hear detail at the top and weight at the bottom at the same time. Brown noise gives you only the bottom. White noise gives you a lot of the top. With pink noise, nothing seems to be missing.
Why Pink Noise Sounds Balanced
Pink noise gets a little quieter as the pitch goes up, but much less than brown noise does. The result is that its sound is spread evenly in the way our ears hear pitch. The deep range, the middle range and the high range each get a fair share. White noise cannot say that: its very top range holds about half of all its sound.
We measured the pink noise on this player. It follows the ideal pink noise pattern very closely, from deep sounds to high ones. It is the most accurate of the five colours on this site.
This even spread is also why sound engineers use pink noise, not white noise, to test sound systems. Play pink noise through a speaker system and a measuring device shows a flat line. So any bump or dip comes from the room or the equipment, not from the test sound. Engineers use it to set up rooms and speakers, and to tune live sound systems. It is the only colour on this site with an everyday job in professional audio.
What Pink Noise Is Genuinely Good At
Being the default. If you do not know which colour you want, start here. It has enough deep sound to take the edge off traffic, enough high sound to soften speech, and not enough of either to be unpleasant. Of the five, it is the least likely to be wrong.
Long sessions without tiring you. Pink noise is soft enough to listen to for hours, but not so deep that it disappears on normal speakers. It is the colour that most often goes from "this is nice" to "I have used this every night for a month".
Standing in for rain. Recorded rain has a balance very close to pink noise, without the separate drops. If you like rain sounds but notice the recording repeating, pink noise gives you much of the same feel with no point where it starts again.
Rooms and speakers you do not control. Because its sound is spread evenly, pink noise copes well with poor speakers. A phone speaker loses the deepest sounds, but what is left still sounds like pink noise. Brown noise on the same speaker barely survives.
The Famous Deep-Sleep Study, Read Properly
Almost every article about pink noise cites one study, and almost none of them describe it correctly. It is worth saying what it actually did, because the gap between the study and how it is used to sell things is unusually wide.
The study is Papalambros and colleagues, Acoustic Enhancement of Sleep Slow Oscillations and Concomitant Memory Improvement in Older Adults (Frontiers in Human Neuroscience, 2017). Its result is real and interesting. During deep sleep, participants had stronger slow brain waves and more, stronger sleep spindles (short bursts of brain activity during sleep). Their memory for words also improved overnight: by about 27% on nights with the sound, against about 6% on "sham" nights with no sound.
Now the details that matter. The sound was very short bursts of pink noise, each 50 milliseconds long (one twentieth of a second), played in groups of five. There was about 1.2 seconds between bursts and about six seconds of silence between groups. The timing was not random. A machine read each person's brain waves live (EEG), and a computer timed each burst to a specific moment in their own slow brain waves. There were thirteen participants, all healthy older adults with an average age of 75, in a sleep laboratory.
So the study tested short sound bursts timed by a machine to a brain rhythm. That is a laboratory method, and pink noise was simply the click it used. It was not "play pink noise while you sleep". Playing pink noise all night is a different thing that this study did not test, and its memory result cannot be carried over to it. With only thirteen people, even the size of the effect should be seen as uncertain.
This is not a reason to avoid pink noise. It is a reason to doubt any product page, including any app listing, that cites this study as proof that its all-night pink noise improves memory. Nobody has tested that claim.
What Pink Noise Is Bad At
Covering heavy, low noise. Pink noise sits between white and brown: deeper than white, but much lighter than brown in the low sounds. Against a lorry running its engine outside or a neighbour's subwoofer, that middle position is the wrong place to be. You end up turning the volume up to cover the rumble, and you add a lot of middle sound you do not need. Brown noise does the job at a much lower volume.
Being the best at one thing. The balance that makes pink noise a good default also makes it the colour least likely to be the best answer to a specific problem. If you know exactly what bothers you, such as rumble, voices or a high whine, one of the other four will usually beat it.
Research support. Apart from the laboratory work above, the evidence for steady pink noise is thin. The 2021 systematic review in Sleep Medicine Reviews looked at steady noise as a sleep aid and rated the evidence as very low quality overall. The 2024 review of many studies in the Journal of the American Academy of Child and Adolescent Psychiatry, which did include pink noise, found a small benefit on lab attention tests for people with ADHD or many ADHD symptoms, and none for anyone else. Both are worth knowing. Neither supports strong claims.
Nothing on this page is medical advice, and pink noise is not a treatment for anything.
Using It Well
Start lower than feels right. Pink noise is easy to set too loud, because it is pleasant. There is no harsh edge to warn you. Set it to the point where the sound you want to cover stops being clear, and leave it there.
Use it to compare. Because it sits in the middle, pink noise is a good place to start when you choose a colour. Listen to it, then try brown in one direction and white in the other. Within a minute, you will know which way you prefer.
Web player and app. The player above runs free 30-minute sessions in your browser, with nothing to install. The app has pink noise too, with no session limit, plus a sleep timer, offline playback, play in the background, and the option to add rain or thunder on top.
How It Compares With the Other Colours
Pink noise is the middle of the set, so it is easiest to describe by its neighbours. White noise is brighter and much better at making speech impossible to follow. Brown noise is deeper and much better against rumble. Green noise starts from pink noise and makes the middle sounds stronger, so it is the closest relative of the five. Blue noise is pink's mirror image: it gets louder as the pitch goes up, not quieter.
If you only ever use one colour, this is the reasonable one to pick.
Frequently Asked Questions
Why is pink noise called 1/f noise?
"1/f" is a short maths description of pink noise. The "f" stands for frequency, which means pitch. Put simply: the higher the pitch, the quieter that part of the sound, in a fixed pattern. We measured this player, and it follows the ideal pink noise pattern very closely. The name describes the maths. It is not a brand.
Does pink noise improve memory while you sleep?
The study behind that claim does not show it. Papalambros and colleagues (2017) used very short bursts of pink noise, each one twentieth of a second long. A machine read each person's brain waves live and timed each burst to a specific moment in their deep sleep. There were thirteen healthy older adults, in a sleep laboratory. That is not the same as playing a sound all night. Steady pink noise through the night has not been shown to have the same effect.
Why do audio engineers use pink noise instead of white noise?
Because their measuring tools split sound into ranges of pitch that match how we hear, and pink noise has the same amount of sound in each range. So if a sound system plays pink noise and the reading is flat, the system is working evenly. Any peak or dip comes from the room or the speakers, not from the test sound. White noise would show a rising line even through a perfect system, so it is no good for the job.
Is pink noise better than white noise for sleeping?
Most people find it more comfortable for long periods. It has much less high, hissy sound, and that is what tires your ears. That is about what people prefer, not medical proof. No good study ranks the colours against each other for sleep. A 2021 review of steady noise as a sleep aid rated the evidence overall as very low quality.
Is pink noise the same as rain sounds?
Not the same, but close. The steady hiss of rain has a balance similar to pink noise, which is why people mix them up. Rain adds separate sounds: single drops, gusts of wind, gutters. Pink noise gives you a sound that stays the same and never starts again. If recorded rain starts to sound repetitive after a few nights, pink noise is a good swap.
Will pink noise mask traffic noise?
Partly. It has more deep sound than white noise, so it covers a busy road better than white noise does. But it has much less deep sound than brown noise. If traffic rumble is your main problem, brown noise will cover it at a much lower volume, which is usually what you want.