SleepLog / Sleep sounds
Free sleep sounds
Sleep sounds mixer
Mix rain, ocean waves, thunder, a fireplace and brown, pink or white noise. Set a timer and they fade out once you're asleep.
Every sound is made live in your browser, so it never loops and there's nothing to download. They're the same sounds as in the SleepLog iPhone app.
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.
Want to know if you snore, too?
SleepLog plays these 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
Which sleep sound should I use?
Use the one you find most relaxing. No sound is proven best: a 2021 systematic review of 38 studies rated the evidence that continuous noise improves sleep as very low quality.
Where sounds differ is in how deep or bright they are. Bright sounds with lots of high frequencies, like white noise, are good at covering sharp noises such as voices or a dripping tap. Low sounds, like brown noise, rain or the sea, cover traffic rumble and feel softer to most people. If you're not sure, start with rain, then try brown noise.
| Sound | What it's like | Good at covering |
|---|---|---|
| Brown noise | Deep, low rumble; most energy in the bass | Traffic, a neighbor's TV, low hum |
| Pink noise | Between brown and white; like steady wind | A mix of low and high sounds |
| White noise | Bright, even hiss, like an untuned radio | Voices, footsteps, sharp sounds |
| Rain | Brown-noise base with light drops | General room noise |
| Thunder | Rain with a slow rumble that rises and falls | Low noise, if you like a storm |
| Ocean waves | Deep noise that swells about every 12 seconds | Low noise; a slow rhythm to breathe with |
| Wind | Soft noise that rises and falls | Mid-range sounds |
| Stream | Brighter running water | Higher sounds, like voices |
| Fireplace | Low base with random crackles | Quiet rooms that feel too silent |
Should sleep sounds play all night?
Not if they only help you fall asleep: a 30 to 60 minute timer covers the time most people take to drift off, and this mixer fades out over the last 30 seconds so the silence doesn't wake you.
Keep them on all night if something in your room or street tends to wake you later on, like early traffic or a partner's snoring. Then keep the volume low. Browsers can pause sound when your phone locks or you switch apps, so for a whole night on your iPhone, the SleepLog app is more reliable: its sounds keep playing while it records the night.
How loud should sleep sounds be?
Quiet: roughly a soft conversation or lower, with the speaker an arm's length or more from your head.
Sound machines can get louder than people expect. A 2014 study measured 14 infant sleep machines and found every one went above 50 dBA at 30 cm, the limit recommended for hospital nurseries, and three went above 85 dBA at full volume. For babies, the authors suggested placing machines as far from the crib as possible, keeping the volume low and running them for short periods. For adults, the same idea holds: set the volume just high enough to soften other noise.
How does this mixer make its sounds?
Your browser makes each sound from random numbers, tens of thousands of times a second, then shapes it: smoothed for brown noise, filtered for pink, with drops, swells or crackles added for rain, waves and fire.
Because nothing is a recording, nothing repeats, and the page works without downloading audio. These are the same recipes the SleepLog iPhone app uses for its sleep sounds. Nothing you play here is sent anywhere.
Questions
Which sleep sound is best for sleeping?
There's no single best sleep sound. A 2021 review of 38 studies found the evidence that continuous noise improves sleep is of very low quality, so pick the sound you find most relaxing. Low sounds such as brown noise, rain and ocean waves are softer on the ear than bright white noise.
Should sleep sounds play all night?
You don't need them all night if they only help you fall asleep. A 30 to 60 minute timer covers most people's time to drift off. If outside noise wakes you later in the night, a sound that keeps playing at a low volume can cover it.
How loud should sleep sounds be?
Keep them quiet, roughly the level of a soft conversation or lower, and put the speaker away from your head. A 2014 study of 14 infant sleep machines found every one went above 50 dBA at 30 cm, the limit recommended for hospital nurseries.
Sources
- 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.
Fall asleep to rain. Wake up knowing how you slept.
SleepLog for iPhone plays your sleep sounds, listens for snoring and gives every night a score.
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