Free · no account · nothing to download
Every colour of noise
White, pink, brown, green, grey, blue, violet and black noise, generated live in your browser — free, with nothing to download and no audible loop.
Layers — mix as many as you like
Tap a second sound to layer it — rain under brown noise, for instance.
Your browser does not support the Web Audio API, so the player cannot run here. Any current version of Chrome, Safari, Firefox or Edge will work.
Pick by problem, not by name
- Traffic or machinery — brown noise, all energy in the low end
- Voices and neighbours — white noise, the widest masking
- Something in between — pink noise, close to steady rain
- Brown feels too muffled — green noise, weighted to the middle
- Even coverage as the ear hears it — grey noise
Generated, not streamed
Most sound sites play a recording on a loop. Loops are the problem: once you notice the repeat point it is hard to stop hearing it, and a sound you are listening to is no longer a sound you can sleep through.
Everything here is synthesised by your browser as it plays. Nothing downloads, nothing streams, there is no repeat to catch your ear — and it keeps working with the connection off.
The colours at a glance
Every colour is defined by how its energy is spread across frequency. Three of them have no formal standard, and we say so rather than inventing one.
| Colour | Spectrum | Sounds like |
|---|---|---|
| White noise | flat (0 dB/octave) | Untuned radio static, a strong hiss |
| Brown noise | falls 6 dB/octave | A distant waterfall, a plane cabin, heavy rain without the patter |
| Green noise | no standard definition | Open countryside at a distance, a steady wash |
| Pink noise | falls 3 dB/octave | Steady rainfall, wind in leaves, a distant river |
| Blue noise | rises 3 dB/octave | A thin, bright hiss with little body |
| Grey noise | no standard definition | White noise with the harsh middle taken out |
| Violet noise | rises 6 dB/octave | A thin, piercing hiss, almost all treble |
| Black noise | no standard definition | Silence, or a barely-there low rumble |
Every colour of noise
White noise
Equal power at every frequency — the bright hiss that masks almost anything.
Play white noise →Brown noise
Deep and low, like a distant waterfall. The most popular colour for sleeping.
Play brown noise →Green noise
Mid-range noise, often described as the background sound of open countryside.
Play green noise →Pink noise
The middle ground: softer than white, brighter than brown. Close to steady rain.
Play pink noise →Blue noise
The mirror of pink: energy rises with pitch, giving a bright, airy hiss.
Play blue noise →Grey noise
Shaped so every frequency sounds equally loud, rather than measuring equally loud.
Play grey noise →Violet noise
The mirror of brown: rises 6 dB per octave into a thin, piercing hiss.
Play violet noise →Black noise
Effectively silence, with almost all energy below what you can hear.
Play black noise →Beyond the colours
Not noise colours in the strict sense, but built from them — and useful for the same reason.
Rain
Steady rainfall with the patter on top — the most requested sleep sound there is.
Play rain →Fan
A box fan running in the corner, without the draught or the electricity bill.
Play fan →Ocean
Slow waves arriving and drawing back, roughly ten to a minute.
Play ocean →Thunderstorm
Rain with distant thunder rolling through at irregular intervals.
Play thunderstorm →Colours you may see elsewhere
Not every colour in circulation has a definition behind it. Rather than invent one, here is what is actually known about the four you are most likely to run into.
- Orange noise
- Turns up in lists without a technical definition. Descriptions vary from "noise with the in-tune frequencies removed" to something close to pink. There is no standard to implement.
- Yellow noise
- Used inconsistently — sometimes as a synonym for pink noise, sometimes for a specific 1/f variant, sometimes for something else entirely. No accepted specification exists.
- Red noise
- This one is real, and it is simply another name for brown noise: an identical spectrum falling 6 dB per octave. See the brown noise page.
- Purple noise
- Also real, and another name for violet noise, rising 6 dB per octave. See the violet noise page.
Questions
What are the colours of noise?
They are names for how a noise spreads its energy across frequency, borrowed from how light is named. White noise carries equal power at every frequency. Pink loses 3 decibels per octave, brown loses 6, and both therefore sound progressively deeper. Blue and violet do the opposite, rising 3 and 6 decibels per octave into a bright hiss. Grey is shaped so every frequency sounds equally loud to human hearing, green is conventionally weighted to the mid-range, and black is effectively silence.
Which colour of noise is best for sleep?
Brown noise is the most common choice, because its energy sits low where the ear is least sensitive and it stays comfortable across a full night. Pink is the balanced middle and the one most often used in sleep research. White masks the widest range, including voices, at the cost of sounding sharper. Green has grown popular recently but has no standard definition. There is no colour that is best for everyone — try brown and pink first.
Is this really free?
Yes, and there is nothing to sign up for. The sounds are generated by your own browser rather than streamed from a server, so there is no bandwidth to pay for and no file to sell you.
Will it keep playing all night?
On a desktop or laptop, yes — leave the tab open and it runs until you stop it. On phones the browser may suspend audio when the screen locks, which is a limitation of the phone rather than of the player.
Do I need to install anything?
No. It is a web page. Nothing is installed, no account is created and no audio file is downloaded — the sound is synthesised as it plays, so it even works with the connection off.