Free online noise generator
A noise generator makes sound from scratch instead of playing a recording. That is what runs on every page of this site.
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.
Most sites that offer white or brown noise are playing you an audio file. A generator does not: it produces the signal mathematically, sample by sample, for as long as you leave it running. White noise is random values. Pink and brown noise are those values filtered to specific slopes. Blue and violet are the same signals differentiated. Nothing is stored, so nothing has to be downloaded and nothing can repeat.
The practical differences are larger than they sound. There is no file to wait for, so the sound starts the moment you press play. There is no loop point, so nothing catches your ear at minute four. The page keeps working when the connection drops. And the whole site, all twenty-odd pages of it, is smaller than a single minute of streamed audio.
Everything is generated with the Web Audio API, which is built into every current browser. Nothing is installed and no account is needed.
Every colour it generates
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 →Questions
What is a noise generator?
A program that creates noise from a mathematical definition rather than playing back a recording. White noise is generated as a stream of random values; the other colours are that stream shaped by filters. Because the sound is computed as it plays, it can run indefinitely without repeating and without downloading anything.
Is a generator better than a white noise recording?
For continuous use, yes, in two specific ways: nothing has to download before it starts, and there is no loop point to notice. Recordings win when you want the character of a particular place or device — a real field recording of rain on a roof has detail no generator reproduces.
Does it use a lot of battery or data?
Data, almost none — after the page loads, nothing further is transferred. Battery use is modest but not zero, since your device is doing the audio work; a laptop or phone left running overnight should be plugged in, which is sensible anyway if you want sound until morning.
Can I use this as a white noise machine?
For most purposes yes. A phone or laptop on this page does the same job as an entry-level machine. A dedicated machine is worth buying if you want physical controls, something that is not your phone, or a device that runs without a screen.