How Loud Should White Noise Be for a Baby? The 50 dB Rule

The short answer: no louder than 50 decibels, measured where your baby's head is, with the speaker at least 7 feet (2 metres) away. That is the guidance from the American Academy of Pediatrics, and it is easy to meet once you know what 50 dB sounds like.

What does 50 dB sound like?

About as loud as a quiet conversation across the room, or a running shower heard from the hallway. Here are some everyday reference points:

Sound	Approx. level
Whisper at 1 m	30 dB
Quiet library	40 dB
Target for baby sleep sound	≤ 50 dB
Normal conversation at 1 m	60 dB
Vacuum cleaner	70 dB
Hairdryer at arm's length	80–90 dB
Occupational limit for adults, 8 h	85 dB

If you have to raise your voice slightly to talk over the sound while standing at the crib, it is too loud.

Why 50 dB and 7 feet?

Because the research on infant sound machines found a real problem. In a 2014 study in Pediatrics, Hugh and colleagues tested 14 popular infant sleep machines and found that every one of them could exceed 50 dB at 30 cm (roughly crib-rail distance), and three could go past 85 dB, the level at which adult hearing-protection rules kick in. The machines were not defective — they were simply capable of being set too loud and placed too close.

The AAP's response was practical: keep the level at or below 50 dB at the baby, keep the device well away from the crib, and use it for sleep rather than all day. The distance matters as much as the volume dial: sound drops by roughly 6 dB every time you double the distance, so a phone that reads 62 dB at 1 metre reads about 56 dB at 2 metres and closer to 50 dB at 4.

How to check the level with your phone

You need two phones: one playing the sound, one measuring.

1. Install any free sound-meter app on the second phone (they are accurate to within a few dB, which is fine for this).
2. Start the sound on the first phone and put it where it will live at night — on a shelf or dresser, at least 7 feet from the crib.
3. Hold the meter phone where your baby's head will be, screen facing up, and read the average level.
4. Adjust the playing phone's media volume until the meter reads 45–50 dB. In Little Napper the volume slider on the Now Playing screen is saved, so you only do this once.

If you only have one phone, the rule of thumb is: the sound should be clearly audible at the crib but not fill the room. Put the phone across the room, set the volume to about a third, and trust the distance.

Is louder ever justified?

Briefly, yes — to break through crying. A newborn mid-cry is producing 100 dB or more at their own ears, and a shush at conversation level cannot compete. Paediatrician Harvey Karp's advice is to shush about as loud as the crying, then lower the sound as the baby calms. Little Napper's volume slider is live, so you can start higher and slide down to the sleep level within a minute. What the AAP is warning about is 70 dB running for eight hours on the crib rail, not thirty seconds of loud shushing.

Does the type of sound change the rule?

No. White, pink and brown noise, rain, a heartbeat or a fan are all measured the same way. Low-frequency sounds like brown noise can feel louder in a small room, so check those at the crib rather than trusting your ear.

FAQ

Can white noise damage a baby's hearing? Only at levels and durations far above the guidance — sustained sound above 85 dB is where hearing damage becomes a concern for anyone. At 50 dB, 7 feet away, for the hours of sleep, there is no evidence of harm.

Should the sound be on all night? It can be, at a safe level. Many parents use a 30-minute timer with a fade-out for settling and reserve all-night sound for light sleepers or noisy homes. Both are one tap in the app.

Is the phone speaker loud enough at 7 feet? Yes. Modern phone speakers reach 80 dB+ at close range; at 2 metres and a third of the volume they sit comfortably in the 45–55 dB band.

This article is general information, not medical advice. Ask your paediatrician about your own baby.

Ready to try it? Little Napper is free on Google Play — 31 sounds, a timer that fades out, and a volume that stays where you set it. See also our guide to white noise for babies.