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Color Noise Explained: All 10 Noise Colors Compared (2026 Guide)

Every noise color explained — white, brown, pink, green, blue, grey, violet, orange, red, yellow. Frequency profiles, what each is best for, and free players for all ten.

2026-01-08·11 min read

There are ten commonly recognised noise colors. Each one distributes sound energy across the frequency spectrum differently, and that difference determines what it's good for.

The short version: brown noise for focus and racing thoughts, white noise for masking and babies, pink noise for sleep quality, green noise for anxiety and gentle background, violet noise for tinnitus. The other five are useful in narrower situations.

This page covers all ten in detail, with the frequency data, what each actually sounds like, and where to go deeper on each one.

How noise colors work

Noise is random sound. What makes one "color" different from another is how the energy is distributed across frequencies — the spectral density.

The naming follows the visible light spectrum. White light contains all wavelengths equally, so white noise contains all audio frequencies equally. Red light sits at the low-frequency end of visible light, so red noise concentrates energy at low audio frequencies. Blue and violet sit at the high-frequency end of light, and so do blue and violet noise.

The analogy isn't perfect — green noise's name is partly coincidence, and brown noise is named after a person rather than a color — but it holds up well enough to be useful.

The frequency slope

Most noise colors are defined by how fast their power drops (or rises) as frequency increases, measured in decibels per octave:

| Noise color | Slope | Character | |---|---|---| | Violet | +6 dB/octave | Sharpest, most treble | | Blue | +3 dB/octave | Bright, hissy | | White | 0 dB/octave (flat) | Even, static-like | | Pink | −3 dB/octave | Balanced, natural | | Brown / Red | −6 dB/octave | Deep, rumbling |

Green, grey, orange, and yellow are defined differently — by a frequency emphasis or a filtering rule rather than a simple slope.

The ten noise colors

White noise

Slope: Flat — equal energy at every frequency. Sounds like: Static, an untuned radio, a fan on high. Best for: Masking a broad range of sounds, baby sleep, office speech privacy, tinnitus.

White noise is the most studied noise color by a wide margin and the default recommendation in clinical and paediatric contexts. Its even spectral coverage means it masks the widest range of disturbances, though that same evenness makes it less efficient than a targeted color for any one specific problem.

Play white noise →

Go deeper:

Brown noise (also called red noise)

Slope: −6 dB/octave. Most energy below 500Hz. Sounds like: A heavy waterfall, an aeroplane cabin, distant thunder. Best for: ADHD focus, deep work, racing thoughts at bedtime, blocking traffic and low-frequency noise.

Brown noise is the most popular noise color for focus, and became widely used in ADHD communities from around 2022. Its depth both masks low-frequency disturbances and provides steady stimulation that helps sustain attention.

Named after Robert Brown and Brownian motion — the random particle movement its mathematics follows — not the color.

Play brown noise →

Go deeper:

Pink noise

Slope: −3 dB/octave. Equal energy per octave. Sounds like: Steady rainfall, rustling leaves, a river. Best for: Deep sleep quality, memory consolidation, long comfortable listening.

Pink noise sits midway between white and brown. It's the spectral profile most common in nature — rainfall, ocean waves, and even heartbeats follow roughly pink distributions — which is why it tends to sound more natural than white noise.

It has the strongest research base of any noise color for sleep quality specifically, as opposed to sleep onset.

Play pink noise →

Go deeper:

Green noise

Emphasis: Mid-range, centred around 500Hz. Sounds like: Wind through trees, a stream, ambient forest sound. Best for: Anxiety, gentle background, all-day listening, people who find white noise harsh.

Green noise concentrates in the band where natural outdoor environments do most of their work. It masks efficiently at low volume and, unlike brighter colors, doesn't trigger the alertness response that high-frequency sound can.

It's the gentlest of the practical noise colors and the usual answer for people who tried white noise and found it grating.

Play green noise →

Go deeper:

Blue noise

Slope: +3 dB/octave. Energy rises with frequency. Sounds like: Escaping steam, a distant sprinkler, a bright hiss. Best for: High-frequency tinnitus, staying alert, masking specific high-pitched sounds.

Blue noise is the inverse of pink noise. It's a poor general sleep choice — the high-frequency emphasis raises arousal — but it's genuinely useful for masking tinnitus and for situations where drowsiness is the problem rather than the goal.

It's also the standard noise used for dithering in digital audio and image processing.

Play blue noise →

Go deeper:

Grey noise

Emphasis: Calibrated to the human equal-loudness contour. Sounds like: White noise without the harsh midrange bite. Best for: All-day listening, open-plan offices, sound-sensitive listeners.

Human hearing isn't equally sensitive at all frequencies — we hear the mid-range far more acutely than the extremes. Grey noise applies the inverse of that curve, so every frequency is perceived at equal loudness rather than being physically equal.

The result is the least fatiguing noise color for very long sessions.

Play grey noise →

Go deeper:

Violet noise (purple noise)

Slope: +6 dB/octave. The steepest high-frequency emphasis. Sounds like: A sharp, high hiss. Best for: High-frequency tinnitus masking, clinical sound therapy.

Violet noise is blue noise taken to its extreme. It's harsh to listen to and has essentially no use for relaxation — but for masking high-pitched tinnitus, its energy sits exactly where the ringing does, which makes it the most efficient option available.

Play violet noise →

Orange noise

Rule: White noise with musically dissonant frequencies removed. Sounds like: Slightly smoother, warmer white noise. Best for: Musicians, audio work, listeners sensitive to dissonance.

Orange noise strips out the frequency relationships that create beating and harmonic clash. The difference from white noise is subtle but real, and for people who found white noise subtly irritating in a way they couldn't name, orange noise usually removes that irritation.

Play orange noise →

Go deeper:

Red noise

Red noise is the same signal as brown noise — different name, same audio. "Red" is the audio-engineering term (by analogy with red light at the low-frequency end of the spectrum); "brown" is the popular term (after Brownian motion).

Play red noise →

Go deeper:

Yellow noise

Emphasis: A peak around 1–2kHz. Sounds like: Energetic, slightly buzzy. Best for: Alertness. Rarely used for relaxation.

The least common of the ten. Yellow noise emphasises the band where human speech and many instruments sit, which gives it a stimulating quality that works against sleep and relaxation but occasionally suits people who need to stay awake.

Play yellow noise →

Brownian noise

Another name for brown and red noise — all three are the same signal. "Brownian" is used most often in physics and audio engineering contexts.

Go deeper:

Choosing by use case

| What you want | Best choice | Second choice | |---|---|---| | Fall asleep faster | Brown | Green | | Stay asleep / mask sounds | White | Brown | | Deeper sleep quality | Pink | Green | | ADHD focus | Brown | Pink | | Deep work sessions | Brown | Grey | | Studying for retention | Pink | Brown | | Anxiety and stress | Green | Pink | | Baby sleep | White | Pink | | High-frequency tinnitus | Violet | White | | Low-frequency tinnitus | Brown | Pink | | All-day background | Grey | Green | | Blocking traffic | Brown | White | | Blocking office chatter | White | Grey | | Staying alert | Blue | Yellow | | Music production background | Orange | Grey |

Comparison guides:

Volume: the thing most people get wrong

Whatever color you choose, volume matters more than the choice itself.

Target 45–60dB — roughly the level of a quiet conversation. Below 60dB is safe for indefinite daily listening. Above 85dB sustained causes hearing damage.

The specific trap: brown noise sounds quieter than it is. Human hearing is less sensitive to low frequencies, so bass-heavy noise played at 75dB can feel like 55dB. People routinely run brown noise 15–20dB louder than they intend.

Check it once with a free decibel meter app, placed where your ears actually sit. This single check prevents most of the problems people attribute to noise itself — ear fatigue, headaches, and poor sleep quality.

For babies, the guidance is stricter: below 50dB, and at least 200cm from the crib.

How long to test before deciding

Give any noise color at least a week of consistent use before judging it.

Two things happen over that week. First, the novelty wears off — the first night with any new background sound feels strange regardless of whether it suits you. Second, and more importantly, your brain builds an association between the sound and the state you're using it for. That association is doing real work by night seven, and it's a large part of why noise helps at all.

If after a week your sleep or focus is measurably worse, that's a genuine finding. Roughly 10–20% of people do worse with any background sound. Try one alternative color, then accept the answer.

Frequently asked questions

Is there a "best" noise color? No. Brown noise is the most popular and the best default for focus and sleep onset, but the right choice depends on what problem you're solving. Use the table above.

Are noise colors scientifically real? Yes. Each is a defined spectral profile used in acoustics and audio engineering, well before any of them appeared in wellness apps. The health claims attached to them vary in evidence quality — pink noise has the strongest sleep research, brown noise the most user reports, green noise the least formal study.

Can I mix noise colors? Yes, and many people do. Brown plus green is a common combination. There's no risk in mixing beyond the usual volume considerations.

Do I need an app or a machine? Usually not. A browser-based generator produces algorithmically generated noise with no loop, which is technically better than most recorded apps and all cheap machines. Read the full comparison.

Is it safe to use every night? Yes, below 60dB. There's no known harm from years of nightly use at reasonable volume, and no meaningful dependency risk beyond becoming accustomed to it.

Try them all

Every noise color on this page is free to play instantly, with no signup and no app:

Brown · White · Pink · Green · Blue · Grey · Violet · Orange · Red · Yellow

The fastest way to find yours is to play three of them back to back for thirty seconds each. Most people have an immediate preference, and that preference is usually right.

Related articles

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Blue noise explained — frequency profile, what it sounds like, and where it's actually used, from tinnitus masking to digital audio dithering. Play blue noise free.

Brown Noise Frequency and Benefits: What It Actually Does

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