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White noise vs pink noise vs brown noise: which is best for sleep?

How white, pink and brown noise differ, what sleep research actually shows, and how to pick a noise color by what keeps you awake: voices, traffic or tinnitus.

By Michal Piják9 min readHow we write these guides

Illustration: layered mountain ridges at night, dark brown in front fading to rose and pale silver in the distance, under a full moon
Illustration: Noctune (AI-assisted)
On this page
  1. What the colors mean
  2. Noise colors compared side by side
  3. What the research shows (and what it doesn’t)
  4. How to choose a noise color for sleep
  5. Volume matters more than color
  6. Questions
  7. Sources

The short answer: none of the noise colors has been shown to be the best for sleep. They differ in where their energy sits, from bright and hissy (white) to soft (pink) to deep and rumbly (brown), and that decides what each one is good at covering up. The research on continuous noise as a sleep aid is thin and mixed, so the honest way to choose is by the sound that bothers you and by what you find pleasant at a low volume.

As a rule of thumb: brown noise for low rumble (traffic, trucks, a neighbor’s subwoofer, a snoring partner’s lower range), pink noise as a balanced default that covers voices without much hiss, and white noise when you need to cover sharp, high sounds and don’t mind the brightness. Keep the volume as low as still does the job.

What the colors mean

Noise colors describe how a random signal’s energy is spread across frequencies. The names are borrowed loosely from light: white light contains all colors equally, so “white” noise contains all frequencies equally.

Noise color spectra from 20 Hz to 20 kHzLine chart, level per hertz in decibels relative to 1 kHz, on a logarithmic frequency axis. White noise is flat at 0 dB per octave. Pink falls 3 dB per octave, brown falls 6 dB per octave, blue rises 3 dB per octave and violet rises 6 dB per octave. Green noise is a band centred on 1 kHz.−30−20−100+10+20+3020501002005001k2k5k10k20kFrequency (Hz, log scale)dBGreen: a band around 1 kHzViolet +6 dB/octBlue +3 dB/octWhite 0 dB/octPink −3 dB/octBrown −6 dB/octNoise color spectra from 20 Hz to 20 kHzLine chart, level per hertz in decibels relative to 1 kHz, on a logarithmic frequency axis. White noise is flat at 0 dB per octave. Pink falls 3 dB per octave, brown falls 6 dB per octave, blue rises 3 dB per octave and violet rises 6 dB per octave. Green noise is a band centred on 1 kHz.−30−20−100+10+20+30201001k10kFrequency (Hz, log scale)dBGreen: ~1 kHz bandViolet +6Blue +3White 0Pink −3Brown −6
Noise colors differ in how their energy is spread across pitch. Lined up at 1 kHz: pink falls 3 dB with every doubling of frequency, brown 6 dB; blue and violet rise. Green has no standard definition; it is drawn as the band around 1 kHz that Noctune generates.Source: Colors of noise (Wikipedia)

White noise

White noise has the same power at every frequency, from deep bass to the highest treble. That sounds balanced on paper, but in practice it isn’t, because of how octaves work. The octave from 100 to 200 Hz is 100 Hz wide; the octave from 5,000 to 10,000 Hz is 5,000 Hz wide. White noise puts equal energy into every hertz, so the upper octaves get far more of it. Add the fact that our ears are most sensitive in the upper midrange, and white noise ends up sounding like TV static or a hissing radio between stations.

Pink noise

Pink noise drops by about 3 dB per octave, which works out to equal energy in every octave. To the ear, that sounds more even: less hiss, more body. Steady rain on a roof or wind through trees are common comparisons, though real nature sounds are never this uniform.

Brown noise

Brown noise (named after Brownian motion, not the color) drops by about 6 dB per octave. Most of its energy sits in the low range, so it sounds like a distant waterfall, strong wind behind a closed window, or an airplane cabin. Many people find it the most soothing of the three, which is subjective but explains its popularity.

The three main colors, generated in your browser with the same code and loudness levels as the app. Start with your volume low and switch between them.

A “deep brown” variant goes further and filters out almost everything above the low range. In Noctune, for example, deep brown is brown noise low-passed at around 200 Hz, so it is a soft rumble with no hiss at all.

Green, blue and violet noise

These are less standardized. Green noise has no formal technical definition; the name is usually given to noise concentrated in the middle of the audible range, which sounds calmer and more “natural” than white noise to many people. Blue noise rises by 3 dB per octave and violet by 6 dB per octave, so both are even brighter than white noise and lean almost entirely into the treble. Few people choose them for a whole night, but some find a thin, high sound easier to tune out than a full-range one, and some people with high-pitched tinnitus prefer them. In Noctune, green is a band around 1 kHz, while blue and violet are the top of the spectrum, above about 4 kHz and 6 kHz.

Noise colors compared side by side

Color Energy distribution Sounds like Covers well Downside
White Equal per hertz, so treble-heavy Static, hiss, a fan on high Sharp, high sounds: clinks, chirps, hallway chatter Can feel harsh or tiring at higher volume
Pink Equal per octave (−3 dB/octave) Steady rain, wind in trees Voices, TV through a wall, general household noise Less effective on deep rumble than brown
Brown Bass-heavy (−6 dB/octave) Distant waterfall, airplane cabin Traffic, trucks, bass, low hum Weak on high sounds; phone speakers struggle with it
Deep brown Only the low range Soft, distant rumble Very low noises, people who hate any hiss Barely masks anything above the low range
Green Middle of the range A soft, rounded “shhh” Midrange sounds, voices Not a standard; varies a lot between apps
Blue / violet Treble only Thin, airy hiss High-pitched sounds; some people with high tinnitus Too bright for most people over a whole night

What the research shows (and what it doesn’t)

Much of what you read online about noise colors and sleep stretches a small set of studies further than they go. Here is what they actually did.

Continuous noise as a sleep aid: weak evidence

The most thorough look so far is a 2021 systematic review in Sleep Medicine Reviews by Riedy, Smith, Rocha and Basner at the University of Pennsylvania. They screened the literature for studies of continuous white or similar broadband noise and sleep, and included 38 articles. The studies varied widely in what noise was played, how loud, how sleep was measured, and what it was compared against. The findings ranged from noise improving sleep to noise disrupting it. Using the GRADE system, the authors rated the quality of evidence that continuous noise improves sleep as very low, and called for better studies with objective sleep measurements before continuous noise is promoted as a sleep aid.

A 2022 systematic review in the Journal of Clinical Sleep Medicine (Capezuti and colleagues) looked at 34 studies with 1,103 participants. Positive sleep outcomes were reported in 6 of 18 white noise studies and 9 of 11 pink noise studies. That looks like a win for pink noise, but the authors concluded there was no strong evidence to support auditory stimulation for sleep, and the study designs were too varied to rank colors with any confidence. They also noted that none of the studies reported adverse effects from short-term use.

The “pink noise boosts deep sleep” studies tested something else

The pink noise and deep sleep claim usually traces back to research like Ngo and colleagues (Neuron, 2013) and Papalambros and colleagues (Frontiers in Human Neuroscience, 2017). Both are interesting, and both are often misdescribed.

In these studies, people slept in a lab wearing EEG electrodes. A computer tracked their slow brain waves in real time and played brief sound pulses timed to a specific phase of each wave. Papalambros used pulses of pink noise in groups of five, followed by pauses, in 13 adults aged 60 to 84. The stimulation increased slow-wave activity during the sound periods and improved overnight word-pair recall compared with a sham night. Ngo’s study of 11 young adults found that well-timed pulses strengthened the slow oscillation and improved memory, while pulses timed to the wrong phase did not help.

That is closed-loop acoustic stimulation: short, precisely timed bursts driven by your own brain activity. A pink noise track playing all night from your phone is a different thing, and these studies don’t tell us it has the same effect.

Continuous pink noise in the lab: a caution

The most rigorous recent test of continuous noise points the other way. In a 2026 study published in Sleep, Basner and colleagues had 25 healthy adults spend seven nights in a sleep lab with polysomnography. Some nights included recorded traffic and aircraft noise, some included continuous pink noise at 40 or 50 dBA, some foam earplugs, and some combinations. Compared with a quiet night, the environmental noise reduced deep (N3) sleep, while the pink noise reduced REM sleep. Earplugs blocked nearly all of the environmental noise effects; pink noise did not. The authors cautioned against widespread, indiscriminate use of broadband noise and said more research on noise color, level and long-term use is needed.

It is one study, with young healthy adults, in a lab. It doesn’t prove that sleep sounds are harmful for everyone. But it is a good reason to keep the volume low and not assume more noise means better sleep. Our article on whether it’s safe to sleep with white noise every night covers volume and timers in detail.

Brown noise has almost no sleep research of its own

Brown noise is popular online, but very few studies test it specifically for sleep. If it works for you, the likely reasons are simple: it covers low noises well, has no hiss, and many people find it pleasant. Focus is a separate question, covered in brown noise for ADHD and focus.

How to choose a noise color for sleep

Since the evidence doesn’t crown a winner, start from the problem you are trying to solve.

Voices, TV and household noise

Speech carries most of what makes it understandable in the midrange and upper midrange. You don’t have to drown it out completely; what keeps you awake is usually your brain trying to follow the words. Pink noise or green noise covers that range without the harsh top end of white noise. White noise also works if you can live with the hiss.

Traffic, trucks, bass and low hum

Low sounds need low-frequency energy to be covered, which white noise mostly lacks at a comfortable level. Brown or deep brown noise is the natural choice. One practical catch: phone speakers can’t reproduce much deep bass, so brown noise on a phone sounds thinner and masks less than you’d expect. A small Bluetooth speaker on the nightstand makes a big difference for brown noise.

The WHO’s community noise guidelines note that noise with a large share of low frequencies can disturb sleep at lower levels than other noise. That applies to unwanted noise like ventilation hum, but it is also a reason to keep a bass-heavy sleep sound modest.

Sudden sounds: a door, a dog, a car alarm

Noise helps most by raising the background level, so a sudden sound stands out less against it. Pink noise is a sensible default here. If the sudden sounds are loud, though, no comfortable volume of noise will cover them, and earplugs may simply work better, as the 2026 Sleep study found.

Tinnitus

There is no single best color for tinnitus. Some people prefer a sound in the same pitch region as their ringing (brighter noise for high-pitched tinnitus), others find pink, brown or nature sounds easier to live with. The American Tinnitus Association’s sound library offers pink, brown and white noise alongside rain and wind. Tinnitus has many causes, so if it is new, one-sided or getting worse, see a doctor or audiologist. More detail in our guide to sounds for tinnitus.

If you just want something soothing

Try each color for a few nights at the same low volume and pay attention to how you feel in the morning, not only how quickly you fall asleep. Many people end up with brown or pink noise, or with a natural sound like rain, which behaves roughly like pink noise with gentle variation.

Volume matters more than color

Whatever color you pick, set the volume just loud enough to take the edge off the sound that bothers you, keep the speaker away from your pillow, and consider a sleep timer so the sound fades out after you fall asleep.

The colors also sit on a continuum: white noise made darker moves toward pink, pink made darker moves toward brown. In Noctune (coming soon to iPhone and Android), each sound has its own volume and a darker/brighter tone control, so you can find the point between colors that suits your room. You can browse all 32 sounds to hear how the colors compare.

Questions

Is pink noise or brown noise better for sleep?

There is no good evidence that one color beats the other for sleep in general. Brown noise is better at covering low rumble like traffic or a neighbor's bass, pink noise is a softer all-rounder, so pick by what you need to mask and by which one you find more pleasant.

Does pink noise increase deep sleep?

The studies behind that claim used short pulses of pink noise timed to the sleeper's brain waves with live EEG monitoring, not a continuous track. A 2026 lab study that played continuous pink noise all night found it reduced REM sleep instead.

Why does white noise sound so harsh?

White noise has equal energy at every frequency, and since each higher octave spans more frequencies, most of its energy sits in the treble. Human hearing is also most sensitive in the upper midrange, so it comes across as a bright hiss.

What is green noise?

Green noise has no formal technical definition. It usually means noise concentrated in the middle of the audible range, which many people describe as a calmer, more natural sound than white noise.

Is white noise or brown noise better for sleep?

Neither is proven better. Brown noise is softer and covers low rumble such as traffic; white noise is brighter and covers sharp, high sounds better. Choose the one that masks your noise at the lowest volume you find pleasant.

Sources

Michal Piják, Founder of Noctune

Michal is an independent developer in Bratislava, Slovakia, and builds Noctune on his own. He writes these guides from published research and official health guidance, and links every source so you can check it.

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