Mix white, pink and brown noise, set the volume and a sleep timer with fade-out. Made live in your browser, no loops.
Pink noise sits between white and brown. Its power falls 3 dB per octave, which gives every octave about the same energy, so it sounds balanced to the ear, a bit like steady rain, rustling leaves or a waterfall. Audio engineers also use pink noise to test speakers and rooms, because equal energy per octave matches how we hear pitch. This page opens with pink noise alone at a low volume. It is made with Paul Kellet's refined filter, which follows the pink slope closely over the range we hear. For a casual listener it is the gentlest starting point: less harsh than white noise, less boomy than brown. Use the slider to add a little brown for warmth. Do not treat this page as a speaker calibration tool. Your device, volume level and room change what you hear, and a proper measurement needs a calibrated microphone. For sleep, set the timer to fade it out.
White, pink and brown noise are three kinds of steady hiss that differ in how their energy is spread across pitch, and this page generates all three live in your browser. White noise has equal power at every frequency, so it sounds bright, like a radio between stations. Pink noise loses 3 dB of power per octave as the pitch rises, which sounds more balanced, like steady rain or a waterfall. Brown noise, also called red noise, loses 6 dB per octave, so it is deep and rumbling, like a strong wind or a far-off engine. These slopes are the standard definitions listed on the Colors of noise page of Wikipedia. Brown is named after Brownian motion, not the colour. Move the three sliders to blend them, or use a Quick mix button for one colour on its own.
Nothing is downloaded and nothing is a recording. Your browser's Web Audio engine plays three buffers of noise computed on the spot when you press Play. White noise is random samples. Pink noise sends white noise through Paul Kellet's refined filter, a published recipe that follows the 3 dB per octave slope closely from about 9 Hz to 22 kHz. Brown noise adds up small random steps with a slight leak, so the signal wanders but never drifts away. Each buffer is 12 seconds long and joined at the ends with a short crossfade, so the loop has no click. Because it is made in your tab, it keeps playing in a background tab and with the screen off on most phones, and it stops when you close the tab.
The sleep timer runs from 15 minutes to 8 hours. Near the end the sound fades out smoothly over the last 30 seconds, or the last quarter of a short timer, and then stops. The fade is scheduled on the audio clock, so it does not depend on the page being in front. Pause freezes the timer too. The volume starts at 40 percent of this page's level, which is low on purpose. Set your device volume first and then raise the slider slowly, because steady noise at a high level over many hours is tiring and, if loud enough, can harm hearing. Keep speakers or earbuds at a level where you can still hear a person talking nearby. Do not use noise to cover sounds you need to hear, such as a baby monitor or a smoke alarm.
Some people say steady noise helps them fall asleep, block out traffic or concentrate on work. Others find it makes no difference or dislike it, and brown noise in particular is often described online as helpful for focus. The research is limited and mixed, and this page makes no medical claim: it is a sound source, not a treatment for sleep problems, ADHD or tinnitus. If you have trouble sleeping or concentrating, speak to a doctor. Treat it as an experiment: try each colour for a few evenings at a low level and keep what you like. Your levels and timer are saved in this browser. Nothing is uploaded, and the page counts visits with Google Analytics, never what you played.
Only roughly. Pink noise is a standard test signal, but this page cannot measure your room, and its level depends on your device. For real calibration use a measurement microphone and room-correction software.
White noise has equal power per hertz, so it is bright. Pink noise falls 3 dB per octave, so each octave has about equal power and the sound is warmer and more like rain.
They differ in slope. White noise is flat, so every frequency has equal power. Pink noise falls 3 dB per octave and sounds balanced, like rain. Brown noise falls 6 dB per octave and sounds deep, like a rumble or strong wind.
Yes. Choose 15 minutes to 8 hours. The sound fades to silence over the last 30 seconds (a quarter of the time for very short timers) and then stops, so it does not cut off suddenly.
On most phones and desktop browsers, yes, because the sound plays through Web Audio. Some phones stop background audio to save battery. If it stops, allow the browser to run in the background or keep the tab open.
The page starts at 40 percent, which is low. Set your device volume to about a third first, then adjust the slider until the noise is just above the room sound. A level that hides speech nearby is too loud for hours of listening.
Nobody can promise that. Some people find the deep sound easier to ignore than white noise, and others prefer pink. Studies are small and mixed. Try 20 minutes of each colour at low volume and keep the one you like.
No. The noise is computed in your browser when you press Play, using 12 second buffers crossfaded at the ends so the loop is not audible. Nothing is fetched, and it works offline once the page has loaded.