Pick a sound. Press play.
Four noise colors × three depths — free, no ads, all night.
Switch depth in the bar below — Deep is the one our app users fall asleep to.
Why depths matter
Most noise sites give you one take of each color. But masking comfort is personal: what feels soothing to one ear feels harsh to another. Our Standard / Medium / Deep variants shift each sound's energy progressively lower — same masking power, less hiss, more rumble. In our sleep apps, the deep variants are what people actually stay on. Try White at Standard, then switch to Deep: same color, completely different feeling.
Not sure which sound to pick?
Take the 60-second quiz
Answer six quick questions about how you sleep and focus, and get the noise color that fits.
Find your sound →White vs brown noise
They sound like cousins but behave differently. The comparison, without the hype.
Read the comparison →White noise for babies
What the research actually says, plus the two safety rules every parent should know.
Read the guide →What is white noise?
White noise is sound that contains every audible frequency at equal intensity — the audio equivalent of white light. To the ear it sounds like steady static, a hard rain on a roof, or an untuned radio. Because it covers the whole frequency spectrum at once, it acts like an acoustic blanket: sudden sounds (a door, a car horn, a snoring partner) stand out less against it, which is why so many people use it to fall asleep, stay asleep, or focus in noisy places.
Research on noise as a sleep aid is genuinely promising but not settled. A 2021 systematic review in Sleep Medicine Reviews (Riedy et al.) found that continuous noise can improve sleep onset in noisy environments, while calling for better-controlled studies. In other words: it clearly helps many people, it is low-risk and free to try, and anyone promising miracles is overselling it. Our approach on this site is to let you test it yourself — the soundboard above is the whole experiment.
White, pink, brown, green — the colors of noise
Not all noise is white. Pink noise rolls off the harsh high frequencies, so it sounds softer — closer to steady rainfall. Brown noise concentrates its energy in the low end: waterfall, ocean swell, airplane cabin — deep-dive in our brown noise guide. Green noise sits in the middle frequencies, like wind through trees — the newest favorite for people who find white too sharp and brown too dark. And each of them goes deeper with the Medium and Deep variants in the player bar.
Take it to bed
The browser player is great for trying things out. For all-night playback with the screen off, background audio and a proper sleep timer, we make Brown Noise Machine — a free iOS app with the same four colors and the same three depths.
Download on the App Store Or find your sound first