What is pink noise?
Pink noise falls away at about 3 decibels per octave as pitch rises, which puts it exactly halfway between the flat spectrum of white noise and the steep bass-heavy slope of brown. That slope is also written as 1/f, and it is not an arbitrary choice: it is the distribution that rainfall, wind and running water tend to follow.
That is the reason pink noise is so often described as the natural sounding one. Your ear has spent a lifetime hearing this slope from weather and water, so it reads as ordinary background rather than as a device in the room.
Pink noise output by frequency
Sounds likeGentle rain, wind through leaves, a distant waterfall.
Best forSustained focus and deep sleep. Not sure? Begin here.
Skip it ifThe room is genuinely loud. White blocks more completely.
Why pink noise helps sleep and focus
Pink noise masks well without concentrating its energy where hearing is most sensitive, which is the practical reason it survives a full night better than white. It is the color most people can leave running for eight hours without noticing it.
It is also the most studied of the noise colors, with published work on both falling asleep faster and on slow-wave sleep and memory consolidation. Treat that literature carefully: the studies are mostly small, several use sound delivered in bursts timed to brain activity rather than a steady stream, and the results do not transfer cleanly to leaving a player on all night. We went through what the evidence actually supports.
If you have never tried noise for sleep and do not know where to start, start here. Pink is the safest first guess for most rooms and most people.
How loud should you set it?
Pink noise is the most forgiving color to set, which is its own small trap: it stays pleasant well past the volume it needs to be. Find the quietest level that still covers the disturbance rather than the loudest level that still feels nice, and you will get the same masking with less on your ears by morning.
Because pink stays pleasant well past the point it needs to be, the useful check is not how it sounds but whether turning it down one notch changes anything you can actually detect. If it does not, leave it down. The full three-step method is here.
How this generator actually works
Real pink noise is more work than most sites are willing to do, so what you usually get is a recording on repeat. Nothing here is recorded: the audio is generated in your browser by a port of the generator that runs inside the Veil app.
The slope comes from the Paul Kellet cascade: six leaky integrators running at staggered corner frequencies, summed together, which approximates a true 1/f response far more cheaply than filtering white noise directly. A small amount of unshaped white is mixed back in to keep the top end from sounding dead, then two low-pass stages at 6 kHz and 8 kHz take off the hiss.
Two independent cascades run at coprime buffer lengths of 30 and 37 seconds and are mixed together. Because those lengths share no common factor, the combined pattern does not come back around until roughly 18.5 minutes have passed, and each loop boundary is crossfaded against real continuation samples rather than faded to silence, so there is no seam to catch.
Try the other colors.
Which color works is personal, and a minute of listening settles it faster than any chart. Each of these is a live generator like this one: White noise Brown noise Green noise Grey noise. Or hear all five side by side. If noise is not the right texture, there are also seven fan sounds.