About Noise Colors

How the sound is made

Every sound on this site is generated by your own browser using the Web Audio API. White, pink and brown noise come straight from their mathematical definitions; violet and blue are those signals differentiated; grey is white noise shaped by the inverse of the equal-loudness contour. Rain, ocean, fan and thunder are built by layering and filtering the same noise with slow modulation, so the texture keeps shifting.

Three of the colours — green, grey and black — have no single agreed definition. We say so on their pages and describe exactly what this player does, rather than presenting one interpretation as the standard.

That approach has three practical consequences: nothing has to download before you can play, there is no repeating loop to notice, and the player keeps working with no connection once the page has loaded.

What this site does not claim

It does not claim to cure insomnia, and it is not written by a doctor. Where the research on a sound is genuinely mixed — which is most of the time — the pages say so rather than picking the flattering interpretation.

This site is about sound, not medicine. Nothing here is a diagnosis or a treatment plan. If you regularly cannot sleep, wake unrefreshed for weeks, snore heavily or stop breathing in your sleep, talk to a doctor — persistent insomnia and sleep apnoea are treatable, and a sound player is not the treatment.

How it is paid for

At the moment it isn't — there are no ads and no trackers on this page. If that changes, it will be stated here plainly, and anything we are paid to recommend will be labelled as such.