White Noise vs Pink Noise vs Brown Noise: Which Is Best for Sleep?

If you’ve ever searched for sleep sounds, you’ve encountered the noise color spectrum — white, pink, brown, and a handful of others. The terminology sounds scientific, and it is, but the marketing around these sounds has raced far ahead of the actual research. Brown noise went viral on TikTok with over 113 million views. Pink noise gets credited with boosting deep sleep and memory. White noise machines have been nursery staples for decades.

But what does the science actually say? Which noise color works best for sleep, and does the distinction even matter as much as the internet suggests?

This guide breaks down the physics, the research, and the practical differences — so you can make an informed choice rather than following a trend.

What makes noise “colored”?

Sound engineers borrowed color terminology from optics. Just as white light contains all visible wavelengths equally, white noise contains all audible frequencies at equal energy. Other noise “colors” describe how energy is distributed differently across the frequency spectrum.

This isn’t a marketing gimmick — it’s a standardized way to describe spectral characteristics. The differences are measurable, objective, and perceptually distinct.

White noise distributes energy equally across all frequencies from 20 Hz to 20,000 Hz. The spectral density is flat, meaning every frequency band carries the same power. Because human hearing perceives higher frequencies as louder, white noise sounds bright and hissy — like television static, a running shower, or a fan on high.

Pink noise follows a 1/f distribution, where energy decreases by 3.01 decibels per octave as frequency increases. Lower frequencies carry proportionally more power, producing a deeper, more balanced sound. To human ears, pink noise sounds fuller and warmer than white noise. Natural examples include steady rainfall, wind through trees, and distant waterfalls.

Brown noise (also called red noise or Brownian noise) follows a 1/f² distribution, with energy dropping 6.02 decibels per octave. This creates a deep, rumbly sound dominated by low frequencies. It resembles heavy surf, strong wind, or the low drone of an airplane cabin. The name comes from Robert Brown, the Scottish botanist who first described Brownian motion — the random movement of particles that this noise pattern models — not from the color brown.

How they sound: a practical comparison

Numbers and spectral curves are useful, but what matters is how these sounds actually feel when you’re trying to fall asleep.

White noise is the most “present” of the three. It commands attention through its brightness and broadband energy. Many people find it effective for masking sharp, sudden sounds — it’s particularly good at covering up voices, door slams, and traffic spikes. The downside is that some people find the high-frequency content harsh or fatiguing over long periods.

Pink noise sits in a sweet spot between coverage and comfort. It masks effectively across the frequency range while sounding more natural than white noise. Most people describe it as warmer and more pleasant for extended listening. Rain, ocean surf, and rustling leaves all approximate pink noise, which may explain why these nature sounds are perennially popular for sleep.

Brown noise feels enveloping and heavy. The dominant low frequencies create a sensation some describe as being wrapped in a warm blanket of sound. It’s less effective at masking high-pitched disturbances (voices, beeping, high-frequency traffic noise) because it has minimal energy in those ranges. But for people who find white and pink noise too bright or stimulating, brown noise can feel deeply calming.

What the research says: an honest assessment

Here’s where things get both interesting and frustrating. The research base for noise colors and sleep varies enormously in quality and quantity.

Pink noise: the strongest evidence

Pink noise has the most robust research support for sleep enhancement. A 2022 systematic review published in the Journal of Clinical Sleep Medicine by Capezuti and colleagues examined 34 studies involving 1,103 participants. Of 11 studies specifically testing pink noise, 9 — or 81.9 percent — reported positive findings for sleep quality.

The most compelling work comes from Northwestern University. In 2017, Dr. Phyllis Zee’s team demonstrated that pink noise pulses synchronized to brain waves enhanced slow-wave activity by 8 percent and improved memory recall by 26.8 percent in older adults. A 2019 follow-up showed benefits for people with mild cognitive impairment as well.

Earlier research from Zhou and colleagues (2012), published in the Journal of Theoretical Biology, found that pink noise significantly increased the percentage of stable sleep time in 40 participants. Brain wave analysis showed that neural activity actually synchronized with the pink noise pattern, reaching the low-frequency oscillations characteristic of deep sleep.

However, a critical caveat emerged in 2025. Dr. Mathias Basner’s team at the University of Pennsylvania found that continuous pink noise at 50 decibels reduced REM sleep by approximately 18 to 19 minutes per night across seven nights. This suggests that the delivery method matters enormously — the Northwestern studies used brief, precisely timed pulses, not continuous playback.

White noise: extensive but mixed results

White noise has been studied more extensively than pink noise, but the results are surprisingly inconsistent. The same 2022 systematic review found that only 6 of 18 white noise studies — just 33 percent — reported positive findings for sleep.

This doesn’t mean white noise is ineffective. It means the research is messy. Studies vary widely in volume levels, delivery methods, participant populations, and outcome measures. White noise’s primary mechanism is sound masking, and that mechanism works regardless of the frequency spectrum — if the white noise is loud enough to cover environmental disturbances, it helps. If the environment is already quiet, adding white noise may not improve sleep and could potentially worsen it.

Where white noise shows clearer benefits is in noisy environments. Hospital studies consistently show that white noise improves patient sleep quality in wards with unpredictable nighttime noise. Neonatal units have used white noise for decades, though a 2021 study in the International Journal of Pediatric Otorhinolaryngology raised concerns that 64 percent of infant sound machines exceed 85 decibels at maximum volume when placed close to the crib.

Brown noise: the evidence gap

Here’s the uncomfortable truth about the internet’s favorite sleep sound: there are no published, peer-reviewed studies testing brown noise for sleep or cognitive performance. None.

The 2024 meta-analysis by Dr. Joel Nigg and colleagues at Oregon Health & Science University, published in the Journal of the American Academy of Child & Adolescent Psychiatry, explicitly stated that no studies of brown noise were identified in their systematic search. Dr. Nigg noted that research on brown noise remains too sparse to draw final conclusions.

This doesn’t mean brown noise doesn’t work. It means we genuinely don’t know whether it works differently from pink or white noise. The millions of people who swear by brown noise for sleep may be experiencing real benefits — but those benefits might come from sound masking generally, from the placebo effect of believing you’ve found “your” perfect sound, or from brown noise’s specific spectral properties. Without controlled studies, we can’t distinguish between these explanations.

Dr. Mathias Basner at Penn Medicine expressed concern about the trend’s public health implications, noting that the gap between popular enthusiasm and scientific evidence is enormous.

The ADHD connection: why noise helps some brains more than others

One of the most interesting findings in noise research is that its effects differ dramatically based on individual neurology.

The 2024 Nigg meta-analysis pooled 13 studies with 335 participants and found a small but statistically significant benefit of white and pink noise for people with ADHD, with an effect size of g = 0.249. For context, this is a modest but reliable improvement — enough to meaningfully help with task performance.

But here’s the twist: for people without ADHD, the same noise showed a negative effect on performance (g = -0.212). The sound that helps one group actively hinders another.

This is explained by the Moderate Brain Arousal model. ADHD is associated with lower baseline levels of neural stimulation — essentially, the brain is under-aroused. External noise triggers a phenomenon called stochastic resonance, where random signals boost the brain’s ability to detect meaningful patterns. It’s like adding static to a weak radio signal — counterintuitively, the noise can make the signal clearer.

For people with typical neural arousal, that same noise pushes the system past its optimal level. The brain is already adequately stimulated; adding more input creates interference rather than enhancement.

This has practical implications for choosing a noise color. People with ADHD or attention difficulties may benefit from louder, more broadband noise (white or pink). People with typical attention may do better with quieter, lower-frequency noise (pink or brown) or with no noise at all.

A 2007 study by Söderlund and colleagues in the Journal of Child Psychology and Psychiatry demonstrated this directly: children with ADHD performed significantly better on memory and verbal tasks with 80-decibel white noise, while their non-ADHD peers performed worse.

Brown noise on TikTok: what happened and what it means

In summer 2022, a series of TikTok videos introduced brown noise to millions of people who had never heard the term. The most viral video, by user @natalyabubb, accumulated 9.7 million views. The hashtag #brownnoise quickly surpassed 113 million views.

Many viewers described profound reactions — a sudden silencing of mental chatter, a feeling of calm they’d never experienced with other noise types. People with ADHD were particularly vocal about the effect, describing it as the first thing that ever quieted their racing thoughts.

These experiences are almost certainly real. The question is whether they’re specific to brown noise’s spectral properties or whether they reflect other factors: the novelty of trying a new sound, the expectation created by persuasive testimonials, the general effectiveness of broadband noise for sound masking, or the particular appeal of low-frequency dominance for certain individuals.

Dr. Dan Berlau at Regis University, who has studied white noise and ADHD, noted that while the evidence for white noise’s benefits is convincing, brown noise science remains understudied. He anticipated the viral trend would prompt more rigorous research — but as of early 2026, that research has been slow to materialize.

Head-to-head comparison: which noise color for what?

Based on the available evidence, here’s an honest comparison across common use cases.

For falling asleep in a noisy environment

Best choice: White or pink noise. Both provide broad frequency coverage for masking. White noise is marginally better at covering high-pitched sounds (voices, electronics). Pink noise is more comfortable for extended listening. Brown noise’s limited high-frequency content makes it less effective at masking the sharp sounds most likely to wake you.

For enhancing deep sleep quality

Best choice: Pink noise. This is the only noise color with positive research specifically on slow-wave sleep enhancement. The evidence is strongest for phase-locked delivery (brief pulses timed to brain rhythms), but even continuous pink noise shows more positive findings than white noise in the systematic literature.

For ADHD focus and concentration

Best choice: White or pink noise. These are the only noise colors tested in the meta-analytic literature for ADHD. Both show modest but reliable benefits for task performance. Brown noise may work through the same mechanisms, but this hasn’t been verified empirically.

For subjective relaxation and anxiety relief

No clear winner. Personal preference dominates here. The limited data on subjective experience suggests that brown noise’s deep, enveloping quality appeals to people seeking a “cocooning” effect, while pink noise’s resemblance to nature sounds appeals to those who find nature calming. White noise tends to score lowest on subjective pleasantness.

For tinnitus management

Best choice: Brown or pink noise. Tinnitus typically manifests as high-frequency ringing. Lower-frequency noise can partially mask tinnitus while being comfortable for extended use. However, clinical tinnitus treatment should involve consultation with an audiologist — noise machines are a coping tool, not a treatment.

Volume matters more than color

One finding that emerges consistently across the literature is that volume control may be more important than noise color selection.

The CDC recommends keeping prolonged sound exposure below 70 decibels. The World Health Organization sets adult limits at 80 decibels for 40 hours per week for personal audio devices and recommends 75 decibels for children. For sleep specifically, Dr. Basner’s research suggests even 50 decibels of continuous noise may affect REM sleep.

At low volumes — say, 30 to 45 decibels — the spectral differences between white, pink, and brown noise are less pronounced perceptually. All three provide some degree of masking, all three create a consistent auditory environment, and the subjective differences shrink. At higher volumes, the differences become more salient, but so do the potential risks.

Practical volume guidelines for sleep:

Place sound sources at least one meter from your head
Start at the lowest volume that provides adequate masking
Use a sleep timer to limit exposure to 30 to 90 minutes
If you can easily have a conversation over the noise, it’s at a reasonable level
Never use noise to cover up sounds that would otherwise be painfully loud — that indicates a volume problem, not a masking problem

How to find your best noise color

The science provides a framework, but individual preference matters enormously. Here’s a systematic approach to finding what works for you.

Start with pink noise for one week. It has the strongest research backing, the broadest appeal, and a natural quality that most people find pleasant. Natural pink noise sources — rain, waterfall, wind — are worth trying alongside synthetic pink noise generators, since natural sounds carry additional restorative properties that pure signal generators don’t.

If pink noise feels too bright, try brown noise. Some people are more sensitive to mid and high frequencies, especially when trying to sleep. Brown noise’s deeper profile may feel more comfortable. Pay attention to whether you’re actually sleeping better or just finding the sound more pleasant — these aren’t the same thing.

If you need strong masking, try white noise. In particularly noisy environments — urban apartments, homes near airports, rooms facing busy streets — white noise’s flat spectrum provides the most comprehensive coverage. It’s less pleasant but more functional for raw masking performance.

Give each option at least three to five nights. One night isn’t enough to assess a sound’s effect on your sleep. Novelty alone can improve or worsen sleep temporarily. You need enough data points to separate real effects from random variation.

Use a sleep timer regardless of which color you choose. The Penn Medicine research on continuous noise and REM sleep applies across noise colors. Using sound as a bridge into sleep — rather than an all-night companion — captures the benefits of masking and relaxation while minimizing potential disruption to sleep architecture.

The bottom line

The hierarchy of evidence for noise colors and sleep is clear: pink noise has the strongest research support, white noise has extensive but mixed results, and brown noise has essentially no controlled research despite massive popular enthusiasm.

But evidence of absence isn’t absence of effect. Brown noise may genuinely work better for some individuals, and the lack of research reflects scientific funding priorities rather than a scientific verdict. Similarly, white noise’s mixed results likely reflect the wide variation in how it’s been studied rather than inherent ineffectiveness.

What the science consistently supports is this: some amount of ambient sound helps most people sleep better in noisy environments. The specific color matters less than the volume, the duration, and the consistency. A sleep timer prevents potential REM disruption. And individual neurology — particularly the ADHD versus neurotypical spectrum — creates genuine differences in who benefits most from background noise.

Choose the sound that feels right, keep the volume low, set a timer, and give it a fair trial. The best noise color for sleep is the one that works for you — and now you have the research to understand why.

Not sure which noise color suits you? Softly lets you explore white, pink, and brown noise alongside natural soundscapes — all with adjustable volume and built-in sleep timers. Find your sound at softly.cc.