Green noise

Mid-range noise, often described as the background sound of open countryside.

Green noise Generated live in your browser

Tap a second sound to layer it — rain under brown noise, for instance.

What is green noise?

Green noise is the colour that has grown fastest in popularity, and also the one with the shakiest definition. Unlike white, pink and brown, it has no agreed mathematical specification. In practice it is described as noise with its energy concentrated in the middle of the spectrum, around 500 Hz — the region where a lot of outdoor ambience sits, which is where the "sound of nature" description comes from. That is how we generate it here, and it is worth knowing that another site may generate something noticeably different under the same name.

This page is a green noise generator: the sound is computed in your browser rather than streamed from a file, so it starts instantly and never reaches a loop point. More on how that works.

Good for

  • People who find brown noise too muffled and white noise too bright
  • A sound close to distant outdoor ambience without rain or birds
  • Anyone curious what the fuss is about — it is the fastest-growing colour

The details

Spectrum
No standard definition — energy concentrated near 500 Hz
Slope
Not defined; this player uses a wide band centred on the mid-range
Sounds like
Open countryside at a distance, a steady wash
Caution
Implementations vary between sites and apps

Questions

What exactly is green noise?

There is no formal standard, which is unusual among the noise colours. White, pink and brown are defined by precise spectral slopes; green is defined by convention as noise weighted towards the middle of the audible range, roughly around 500 Hz. Some sources tie it to the centre of the human hearing range, others to measurements of natural ambient sound. Because the definition is loose, green noise from two different sources can sound quite different.

Is green noise better for sleep than brown noise?

There is no research comparing them directly, so anyone claiming a winner is guessing. What can be said is what they sound like: green sits in the mid-range and reads as more open and airy, brown sits low and reads as deeper and more enveloping. Try both for a few nights each.

Why has green noise become popular?

Largely through social media rather than research — it spread the same way brown noise did a couple of years earlier. That is not an argument against it; it is just worth separating popularity from evidence. If it works for you, it works.

Every colour of noise

Beyond the colours

Not noise colours in the strict sense, but built from them — and useful for the same reason.