Only the middle of the spectrum
Green noise is not an official color like white or pink noise. The name became popular with sleep apps and videos, and it usually means a noise centered on the middle frequencies, the range where voices, birds and most everyday sounds live. Our version starts from pink noise and passes it through a band filter centered around 500 Hz, then cuts the treble above about 2,500 Hz. You get a soft, full sound with no deep rumble and no hiss.
Many people describe it as the sound of nature in the background: a distant waterfall, wind in a forest, a steady breeze. It is less bright than white noise and less heavy than brown noise. The bars above show its shape: a hump in the middle, low on both sides.
Who likes green noise
People who find white noise too sharp but brown noise too boomy often settle on green noise. Because it has little energy in the very low frequencies, it also sounds good on a phone or a laptop speaker, which cannot play deep bass anyway. It is a good choice for reading, studying, or falling asleep in a room where the sounds that bother you are voices, a TV next door or footsteps.
| Noise | Where the energy is | Feels like |
|---|---|---|
| White | Equal at every frequency | Bright hiss |
| Pink | Equal in every octave (−3 dB per octave) | Steady rain |
| Green | Around 500 Hz, little bass or treble | Soft, rounded, open |
| Brown | Mostly low (−6 dB per octave) | Deep rumble |
Suggested settings
Green noise does not need to be loud. Start at volume 3 or 4 and go up only until the sounds that bother you blur into the background. For falling asleep, set the timer to 30 or 45 minutes: the last minutes fade out slowly, so the end does not wake you. For a work session, 1 hour is a good length, then take a break. On a phone, plug it in for long sessions and go full screen: when you stop touching it, the display dims.
Research on green noise as such is close to nonexistent. What we know is that a steady sound helps mask sudden noises. If green noise is the one you stop noticing, it is the right one for you.