White Noise vs Pink Noise vs Brown Noise for Babies

All three are "broadband" noise — sound spread across the whole hearing range — and all three mask the sudden noises that wake babies. They differ in where the energy sits: white is bright and hissy, pink is balanced like rain, brown is a deep rumble. Which one works is a matter of the baby's preference, not science, so the practical advice is to try each for a night and keep the one your baby settles to.

What do the colours mean?

They describe how loud each frequency is relative to the others.

Colour	Energy per octave	Sounds like	Feels like
White	Equal at every frequency	TV static, a running tap	Bright, hissy, "sharp"
Pink	Falls 3 dB per octave	Steady rain, wind in trees	Balanced, natural
Brown	Falls 6 dB per octave	A distant waterfall, a jet at cruise	Deep, low, "soft"

Because human hearing is more sensitive to high frequencies, white noise sounds harsher than its flat spectrum suggests. Pink noise is often described as what white noise "should" sound like — every octave feels equally loud. Brown noise (named after Brownian motion, not the colour) drops the treble almost entirely.

Which noise is best for a newborn?

Start with pink or a womb sound; move to white if the baby needs more masking. Newborns spent nine months inside a low-frequency environment — blood flow, heartbeat, muffled voices — so the deeper end of the spectrum is more familiar. That is why Little Napper's Newborn row has womb and heartbeat first, and why pink noise is a good default. White noise is the strongest masker for a house with older children or thin walls, and some babies clearly prefer its brightness.

The 1990 study that is quoted everywhere (Spencer et al., Archives of Disease in Childhood) used white noise and found 80 % of newborns fell asleep within five minutes versus 25 % without. There is no equivalent head-to-head study of the colours in infants; the pink-and-brown preference is parent-reported.

Does brown noise help babies?

It can, especially for babies who already settle to a fan, a car engine or a washing machine. Brown noise is the closest synthetic match to those hums. Two cautions: it feels louder in a small room because low frequencies carry through walls and furniture, so measure it at the crib; and it masks high-frequency sounds (a doorbell) less well than white noise does.

Does the colour change the safety rules?

No. Whatever the colour, keep the level at or below 50 dB where the baby sleeps, the phone at least 7 feet away, and use it for sleep rather than all day. Brown noise is the one to double-check with a meter, because your ear underestimates it.

How to try all three in a week

1. Nights 1–2: pink noise at a level you can talk over. Note how long settling takes.
2. Nights 3–4: white noise at the same measured level.
3. Nights 5–6: brown noise, checked at the crib with a meter app.
4. Night 7: keep the winner and favourite it in the app so it is the first tile on the screen.

If nothing separates them, keep pink — it is the easiest for the adults in the room to sleep next to.

FAQ

Is pink noise safer than white noise for babies? Not inherently. At the same measured level they are equally safe. Pink noise is gentler on the ear because it has less treble, which is why some parents assume it is "safer".

Can I mix noise with a heartbeat? Little Napper plays one sound at a time, but the womb sound already includes a heartbeat under a low whoosh — that is the mix most parents are after.

Why does my baby wake when I switch sounds? Any change in the sound environment can wake a light sleeper. Switch between sounds before sleep, not during.

This article is general information, not medical advice.

All three colours are in Little Napper, free on Google Play. Guides: white noise · pink & brown noise.