Time & date
White noise generator
Pick a sound — white, pink or brown noise, or a synthesized rain, surf, fan or airplane-cabin texture — layer up to three, and press Play or the Space bar.
Sounds
Up to 3 layersEqual power at every frequency — bright and hissy.
Starts at −20 dB and fades in over 3 seconds. Set your device volume low first, then raise it slowly.
Sleep timer
No timer — plays until you pause it.
Hearing safety: keep the volume moderate — quieter than normal conversation is plenty for sleep — and avoid long sessions in headphones at high levels. This is not a medical device.
For babies: follow paediatric guidance. A 2014 study in the American Academy of Pediatrics journal Pediatrics found that infant sleep machines can exceed safe noise limits at full volume, and advised placing them as far from the baby as possible — never in or on the crib — at a low volume, and not running them all night.
Space plays and pauses · all sound is generated in your browser — nothing is downloaded or uploaded
Works in your browser. No account needed.
Frequently asked questions
What is the difference between white, pink and brown noise?
They differ in how their power is spread across frequencies. White noise has equal power per hertz — a flat spectrum — so each octave holds twice the energy of the one below it and it sounds bright and hissy. Pink noise has power proportional to 1/f, falling 3 dB per octave (10 dB per decade), so every octave holds the same energy and it sounds softer and more balanced. Brown (or red) noise falls 6 dB per octave (20 dB per decade), power proportional to 1/f², which leaves a deep rumble. “Brown” comes from Brownian motion, named after the botanist Robert Brown — not from a colour. This tool's tests measure about 0, −3 and −6 dB per octave for the three.
Are the rain, ocean, fan and airplane sounds real recordings?
No. Everything is generated in your browser from random numbers with the Web Audio API — no audio files are downloaded. The textured sounds are synthesized approximations: rain-like is band-limited pink noise with random droplet ticks, ocean-like surf is brown and white noise whose loudness and brightness swell with two slow, out-of-step cycles, fan is low-passed pink and brown noise with a gentle oscillating sweep, and airplane cabin is a steady low-frequency roar. They are designed to be pleasant and steady, not to fool you into hearing a real storm or beach.
Does white noise help you sleep?
It can help some people by masking sudden sounds — traffic, a neighbour, a snoring partner — that would otherwise wake them, because a change in noise is more disruptive than a steady level. The research is not conclusive: a 2021 systematic review in Sleep Medicine Reviews rated the evidence that continuous noise improves sleep as very low quality. If you use it, keep it quiet and use the sleep timer so it is not running all night. Brown or pink noise is often preferred for sleep because it has less of the high-frequency hiss.
Is white or brown noise good for focus?
Many people find steady noise helps them concentrate in a noisy office or café by covering speech, which is especially distracting. Studies are mixed: some found that moderate noise helped attention in children with ADHD traits, while others found it hurt performance in people who concentrate well already. Try it for a few sessions at a low volume and judge for yourself.
Can I use it for tinnitus?
Some people with tinnitus find that a quiet background sound makes the ringing less noticeable, and sound therapy is one of the approaches audiologists use. But this generator is not a medical device and not a treatment. Set the level below your tinnitus so it blends rather than covers, and see a doctor or audiologist about tinnitus — urgently if it came on suddenly, is in one ear only, pulses with your heartbeat or comes with hearing loss or dizziness.
Will it keep playing when my screen is off?
It depends on the browser. In Chrome, Edge and Firefox the sound is played through a media element, so the browser can offer play and pause in its media controls or on the lock screen, and on Android it usually keeps playing with the screen off. On iPhone and iPad, Safari may pause web audio when the screen locks or you switch apps; if that happens you will see a note and can press Play again. The reliable option on any device is to tick “Keep the screen awake” and turn the brightness down. Desktop browsers keep playing in a background tab.
About this tool
This generator makes three classic noise colours and four textured sounds entirely in your browser. White noise is a stream of independent random samples. Pink noise is white noise passed through Paul Kellet's filter, which follows the ideal −3 dB per octave slope closely across the audible range. Brown noise is white noise integrated with a slight leak, giving −6 dB per octave above about 15 Hz without drifting off-centre. Each sound is a 12-second stereo loop with independent left and right channels, crossfaded end to start so the loop point has no click, and played from a random point each time.
The textured sounds combine those noises with filters and slow modulation. Rain-like adds about 140 short random ticks per second to band-limited pink noise, with a slow swell like gusts of wind. Ocean-like surf moves a low-pass filter and the volume together using two slow cycles, about 12 and 20 seconds long, that drift in and out of step so the waves do not repeat exactly. Fan and airplane cabin are low, steady roars, the fan with a gentle oscillating sweep. They are honest approximations, not recordings of real rain or oceans.
Levels are chosen to be safe by default. Every loop is normalised to the same RMS level, the master volume starts at −20 dB, playback fades in over three seconds, and a limiter stops three layers at full volume from clipping. The sleep timer is booked on the audio clock rather than a page timer, so the one-minute fade-out still happens when the browser slows down background tabs. Pausing fades out briefly instead of cutting off.
Keep the volume moderate: quieter than normal conversation is enough for sleep, and long sessions in headphones at high levels can damage hearing. For babies, follow paediatric guidance — a 2014 study in the American Academy of Pediatrics journal Pediatrics found that infant sleep machines can exceed recommended noise limits at full volume, and advised placing them as far from the infant as possible, never in or on the crib, at a low volume and not running all night. Nothing you do here is uploaded; your mix, volume and timer are stored only in this browser.