SleepLog / Sleep sounds / White noise
White noise player
White noise for sleep
An even hiss, like a fan or an untuned radio, that covers voices and sudden sounds. Press Play and set a timer.
This white noise is made live in your browser with the same recipe as the SleepLog iPhone app, so it never loops. Too bright? Switch to pink or brown noise in one tap.
Pick a sound or two, then press Play. The timer fades them out over the last 30 seconds.
On a phone, your browser may stop the sound when the screen locks. The SleepLog app keeps playing all night.
White noise and a snoring check, in one app
SleepLog plays sleep sounds while it listens for snoring, coughing and sleep talking, then shows you the night in the morning.
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Updated 22 October 2026
What is white noise?
White noise is random sound with equal energy at every frequency, which the ear hears as a bright, even hiss.
White noise carries more energy in the high octaves than pink or brown noise, and our ears are most sensitive in the upper-middle range, so it sounds bright and sharp. A fan, an air purifier or the hiss between radio stations are everyday examples.
Does white noise help you sleep?
It can help by covering sounds that would otherwise wake you, but the evidence is weak: a 2021 review of 38 studies rated the evidence that continuous noise improves sleep as very low quality.
White noise works by masking. A door closing or a voice in the hall stands out less against a steady background. That is most useful in noisy places, like a city apartment or shared room. If your bedroom is already quiet, you may not need it at all. Try it for a few nights and keep it if you sleep better.
White noise vs pink noise vs brown noise
White noise is the brightest of the three; pink noise drops the highs a little and brown noise drops them a lot, so they sound softer.
| Brown noise | Pink noise | White noise | |
|---|---|---|---|
| Loudness as pitch doubles | Drops about 6 dB | Drops about 3 dB (equal energy in every octave) | Stays the same |
| Sounds like | Distant thunder, a strong waterfall | Steady wind, rain on leaves | An untuned radio, a fan on high |
| Feels | Deep and soft | Balanced | Bright, can feel harsh |
| Best at covering | Traffic, rumble, a TV next door | A mix of everyday noise | Voices, footsteps, sharp sounds |
Many people who find white noise harsh prefer pink or brown noise. You can switch in the player above, or mix white noise with rain for something more natural.
Is white noise safe for babies?
It can be used, but keep it quiet and far from the crib: a 2014 study found all 14 infant sleep machines it tested went above 50 dBA at 30 cm, the limit recommended for hospital nurseries.
Three of those machines went above 85 dBA at full volume. The authors suggested placing machines as far from the baby as possible, keeping the volume low and limiting how long they run. A phone or speaker playing this page needs the same care.
Questions
What is white noise?
White noise is random sound with equal energy at every frequency. It sounds like a bright, even hiss, similar to a fan on high or an untuned radio.
Is white noise or pink noise better for sleep?
Neither is proven better. White noise is better at covering voices and sharp sounds; pink and brown noise sound softer. A 2021 review of 38 studies rated the evidence that continuous noise improves sleep as very low quality, so pick the one you find most comfortable.
Should I play white noise all night?
Only if something wakes you later in the night. If it just helps you fall asleep, a 30 to 60 minute timer is enough. Keep the volume low and the speaker away from your head.
Sources
- Kasdin NJ. Discrete simulation of colored noise and stochastic processes and 1/fα power law noise generation. Proceedings of the IEEE. 1995;83(5):802–827.
- Riedy SM, Smith MG, Rocha S, Basner M. Noise as a sleep aid: a systematic review. Sleep Medicine Reviews. 2021;55:101385.
- Hugh SC, Wolter NE, Propst EJ, Gordon KA, Cushing SL, Papsin BC. Infant sleep machines and hazardous sound pressure levels. Pediatrics. 2014;133(4):677–681.
- SleepLog iPhone app, sleep sound recipes (SleepSoundPlayer), checked 22 October 2026.
White noise tonight. Your night, heard tomorrow.
SleepLog for iPhone plays sleep sounds, listens for snoring and gives every night a score.
Scan with your iPhone camera to get SleepLog