White noise
Equal energy across the whole range. Bright and even, the classic choice for covering voices and street noise.
Timer
Generated in your browser with the same code as the app, nothing to download. Start with your volume low. Keep this tab open.
About this sound
White noise is a stream of random values with the same power at every frequency. Because each higher octave spans more frequencies than the one below, most of that energy lands in the treble, which is why it sounds like a bright hiss or radio static.
Nothing here is a recording. The player builds the noise from random numbers the moment you press play, using the same code as the app: a 30-second buffer of random samples, with the loop point crossfaded over half a second so there is no tick. Its level is trimmed to match the recorded sounds, so switching from rain to white noise does not jump in volume.
How people use it
White noise is the classic choice for covering voices, a TV through the wall, or sharp sounds from the street, because it has plenty of energy in the range where speech sits. Many people find it harsh on its own; if so, try pink or brown noise first.
Keep it as quiet as still does the job and put the phone or speaker across the room, not by your pillow. For a nursery, the cautious way is low volume, the speaker well away from the crib and a sleep timer rather than all night. The app's timer fades out slowly (30 seconds to 10 minutes), or can just turn the sound down for the rest of the night.
Questions
Is white noise bad for you?
At the low volumes used for sleep, hearing damage is unlikely. Sleep can be disturbed at much lower levels than hearing is harmed, so keep it as quiet as still works, measured at your pillow.
Why does white noise sound so harsh?
Equal energy per hertz means the upper octaves get most of it, and our ears are most sensitive in the upper midrange. Pink noise turns the highs down and sounds softer.
Can I hear where it loops?
No. The noise is random and generated fresh every time you press play, and the 30-second buffer has a crossfaded seam, so there is no pattern to catch.
Get white noise on your phone
Nightwool is coming to iPhone and Android. One e-mail when it launches, then we delete the list.