White noise for babies: how to use it safely

Does white noise help babies sleep

White noise helped newborns fall asleep faster in a small randomised trial, and that trial is still the main evidence. In 1990 Spencer and colleagues published a study in Archives of Disease in Childhood with 40 newborns aged 2 to 7 days, divided into two groups of 20. With white noise, 16 of 20 babies (80 %) fell asleep within five minutes; without it, 5 of 20 (25 %) did. According to the American Academy of Pediatrics, the sound source was placed 30 to 50 cm (12 to 20 inches) from the baby's head.

The authors concluded, carefully, that white noise "may help mothers settle difficult babies". The study measured how fast babies fell asleep in the first days of life, not how long they slept, how they slept over months, or whether the effect lasts. It is a good reason to try white noise to settle a baby, and not a reason to play it all night, every night, for a year.

Every baby is different. Some settle immediately with a steady sound; others are not affected, and a few seem to be bothered by it. Watch your own baby rather than the average.

White noise for colic and crying

White noise reduced crying in colicky babies more than rocking did in one randomised trial. Sezici and Yigit (Journal of Clinical Nursing, 2018) studied 40 one-month-old babies with colic in Turkey. Each baby had one week in which parents swung or rocked them when they cried, and one week in which they played white noise; the order was randomised. In the white-noise week babies cried less each day and slept more than in the rocking week. The American Academy of Pediatrics notes that the noise in that study was set at 55 dB, 30 to 50 cm from the baby.

Colic is exhausting, and anything that shortens crying matters to parents. White noise does not treat colic, but it gave parents in this study a calmer week. If a baby cries inconsolably, has a fever, feeds poorly, vomits or seems unwell, see a doctor: a sound is not the answer to those.

Is white noise safe for babies

White noise can be used safely for babies if it is quiet, far from the cot and not left on for long, but baby sound machines are often far louder than that. In 2014 Hugh and colleagues (Pediatrics) measured 14 infant sleep machines at maximum volume at 30, 100 and 200 cm, with the values corrected for the ear canal of a 6-month-old. All 14 exceeded 50 dBA at 30 cm, the recommended noise limit for hospital nurseries. Thirteen of 14 exceeded it even at 200 cm. Three exceeded 85 dBA at 30 cm, a level that over more than 8 hours would exceed occupational noise limits for adults.

Two gaps in the research matter as much as the measurements. When the American Academy of Pediatrics reviewed the infant white-noise studies in 2023, it noted that none of them commented on possible adverse effects. And no study has looked at the long-term effects of nightly white noise on a baby's hearing or development. The absence of evidence of harm is not evidence of safety; it is a reason to use the lowest dose that works.

These are maximum-volume figures. The point is not that machines must be avoided, but that the volume knob matters a great deal, and that distance alone does not make full volume safe.

AAP white noise guidelines for babies

The American Academy of Pediatrics advises that if a sleep machine is used, it should be placed as far from the baby as possible, set as low as possible, and run for a limited time. This advice appears in the 2023 technical report on preventing excessive noise exposure in infants, children and adolescents (Balk and colleagues, Pediatrics), prepared by the Academy's Council on Environmental Health and Climate Change and its Section on Otolaryngology–Head and Neck Surgery. It repeats the recommendations of the Hugh 2014 study.

In practice the advice comes down to four rules:

• Distance: as far from the baby as the room allows. Never in the cot and never on the cot rail.
• Volume: as low as possible. The goal is a soft background, not a sound that drowns everything.
• Time: use a timed shut-off, or switch the sound off once the baby is asleep.
• Watch the baby, not the machine: if the baby settles without it, you do not need it.

How loud should white noise be for a baby

White noise for a baby should be as quiet as still helps the baby settle, and measured at the cot it should stay below the 50 dB limit recommended for hospital nurseries. That is the limit Hugh and colleagues used as their reference. In the colic trial the sound was set at 55 dB at 30 to 50 cm, so the studies that found a benefit did not use loud sound.

For older children and adults there is also a weekly safe-listening limit. The WHO and ITU standard H.870 (2019) sets 75 dB for 40 hours a week for children, lower than the 80 dB for adults. A sound played through every nap and every night adds up to far more than 40 hours, so a baby's sound should stay well below that level.

You can check the level yourself. Sound meter apps on phones are not laboratory instruments, but they give a rough reading that is far better than guessing.

• Start the white noise at the lowest volume.
• Hold a phone with a sound meter app where the baby's head will be.
• Raise the volume only until the baby settles, and check that the reading at the cot stays under 50 dB.
• A simple check without an app: if you have to raise your voice to talk over it beside the cot, it is too loud.

How far should a white noise machine be from a baby

A white noise machine should be as far from the baby as the room allows, and never in or on the cot. The studies that found a benefit placed the sound 30 to 50 cm from the baby, but at that distance loudness matters most: in the Hugh study every machine at full volume exceeded the nursery limit at 30 cm. Moving the source further away and keeping the volume low is the combination the American Academy of Pediatrics recommends.

A practical place is a shelf or a chest of drawers on the other side of the room, or near the door. The sound fills a small room easily at a low level, and a longer distance means small changes of the volume knob have less effect at the baby's ear. If you use a phone, the same rule applies: not in the cot, not on the mattress, not tucked under the cot sheet.

Should white noise play all night for a baby

White noise does not need to play all night for a baby; the American Academy of Pediatrics advises a timed shut-off or turning it off once the baby is asleep. The studies that found a benefit measured falling asleep and crying, not all-night sleep, so the evidence supports using white noise to settle the baby, not to keep sound on until morning.

The player on this page starts with plain white noise at a moderate level. Its timer can be set to 15 minutes, 30 minutes, 1 hour, 2 hours or 8 hours, and at the end the sound fades out over the last minute instead of stopping abruptly. For most babies 15 or 30 minutes is enough to cover falling asleep.

White noise and safe sleep for babies

White noise is a settling aid, not a safe-sleep measure, and it does not change any of the basic safe-sleep rules. Follow the safe-sleep advice of your health service: a baby sleeps on the back, on a firm flat surface, in their own cot, with nothing else in it.

The device itself belongs to the safe-sleep picture. A sound machine, a speaker or a phone is an object, and objects do not belong in the cot. Keep charging cables well out of reach, do not hang a machine on the cot rail, and do not place it where it could fall into the cot. A sound source across the room is safer in every sense: quieter at the baby's ear, and nothing near the baby's face.

White noise also does not replace watching and listening. If the sound is loud enough to cover your baby's cries on a baby monitor, or to stop you hearing them from the next room, it is too loud.

White, pink or brown noise for babies

The baby studies used white noise, and no study has compared white, pink or brown noise for babies. So there is no evidence that a deeper colour works better or worse. White noise has equal energy across all frequencies and sounds like a steady hiss. Pink and brown noise are softer and deeper.

If your baby settles with any of them, choose the one that works at the lowest volume. Some parents find brown noise more pleasant for themselves, which matters when it plays in a shared room. The rules on distance, volume and timer are the same whichever colour you pick. The white noise page and the colors of noise page describe the colours in detail.

Using a phone as a white noise machine for a baby

A phone works well as a white noise machine for a baby if it is placed away from the cot and set up so that nothing interrupts the sound. The main advantage over a dedicated machine is control: you can see the timer, set the level precisely and check it with a sound meter app on the same phone.

• Turn on do-not-disturb or flight mode, so that calls and notifications do not sound in the middle of a nap.
• Start the sound, set the timer, then turn the screen off; the sound keeps playing.
• Put the phone across the room, never in the cot or on the mattress, and keep the charging cable out of reach.
• Use the phone's own speaker at a low level rather than a large external speaker turned up.
• Test the whole setup once while the baby is awake, so you know how loud it really is at the cot.

How to stop using white noise with a baby

You can stop using white noise gradually by lowering the volume and shortening the timer over a week or two. No study has looked at whether babies come to depend on white noise, and there is no evidence that using it for a period causes a lasting habit. Still, a sound that is needed for every nap can be inconvenient when you travel or when the phone is elsewhere.

A gentle way: lower the volume a little every few days until it is barely audible, then move from 30 minutes to 15, then to none. Many parents also stop naturally as the baby grows and settles more easily. If your baby sleeps well without it, there is no reason to start again.