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Although most parents swaddle their babies these days, it amazes me how few use white noise to boost their little one’s sleep. White noise works miracles with fussy babies and is an amazingly powerful cue for falling asleep…and sleeping longer. This special sound is as important as swaddling. In fact, a 40-baby study found that white noise helped 80% fall asleep in just 5 minutes! Another study found that white noise significantly decreases the duration of crying and increases sleepytime in colicky babies. Even the American Academy of Pediatrics (AAP) agrees that white noise can be helpful at improving sleep. Let me explain how it all works—and how white noise can work for you and your little one!

Why does white noise calm babies?

White noise is a key tool in the Happiest Baby sleep approach. It helps turn on your baby’s calming reflex, or their built-in “reset button” to calm crying and bring on sleep. The best sound for calming fussing is a rough, slightly harsh noise that’s nearly as loud as your little one’s crying. You can provide this sound simply by putting your mouth close to your baby’s ear and making a strong “Shhhhhhhhhhhhhhh” sound. But white noise is not just for calming crying. A more rumbly, low pitched sound promotes sleep as well. And since it’s pretty tricky to “Shhhhhhhhhhhhhhh” in your tot’s ear for all naps and nights, turning to a white noise machine is a good idea!

How does white noise help babies sleep?

White noise helps to create a comforting environment for your baby, like a cozy teddy bear of sound, letting your little one know when it’s time for sleep. The reason white noise is so effective is because it mimics the sounds your baby heard in the womb. White noise lulled them to sleep then…and can lull them to sleep now. White noise also covers over outside distractions—like a noisy truck or a TV playing in the next room—and inside discomforts, like teething and mild hunger, further bolstering ZZZ’s. 

To start using white noise, play the sound in the background during your baby’s sleepytime routine. Soon, this will signal to your sweetie that their glide into dreamland is just minutes away. And this will continue to work even after Baby’s calming reflex gradually disappears by 3 to 4 months. By then, your infant will have learned that white noise means that bedtime has come. So, every time you turn the white noise on, your precious bub will think, “Oh yeah, I recognize that sound…now I’ll have nice sleep.” 

What’s the best white noise for helping babies sleep?

While many white noise machines and apps feature 20+ sounds, only continuous, monotonous, and low-pitch sounds work to lull babies to sleep. (Inconsistent sounds, like waves or birds chirping simply don’t work.) And the very best white noise sounds for your baby’s sleep mimic the loud rumbly sounds they heard for nine months in the womb. To make sure you’re giving your little one the just-right sleep sounds, I recommend using our award-winning SNOO bassinet and/or a white noise device like SNOObie or SNOObear...where you will always find the right sounds! Here are best baby sleep sounds that were specially engineered for SNOO, SNOObear, and/or SNOObie

  • Rain: Peaceful and soothing for infants and parents
  • Strong hair dryer: Calms fussy babies
  • Fast and vigorous white noise: The best sound for the fussiest babies
  • Train: A calming heartbeat-like rhythm
  • Shush: Imitates exactly what experienced parents do to calm fussing

Can white noise played through the phone be effective?

Some parents play white noise on their smartphones, which can be okay if it’s the right sounds, like the Happiest Baby SNOO sounds download. But it’s important to remember that phones release microwave radiation, so you’d need to make sure you put your phone on airplane mode when you place it near your baby. Another drawback: Telephone speakers make a more hissy or tinny noise…not the deep, rumbly sound that best mimics the womb…and best boosts sleep. When you need a portable white noise machine, I recommend SNOObear. I designed SNOObear to feature the same super-effective sounds babies love in SNOO, plus a few extras. What I love about SNOObear is that it’s great to use when your baby is out of bed, to soothe fussing during diaper changes, feeding, trips outside in a stroller or sling, or during “witching hour.” And for babies and toddlers, it’s also a great helper during car rides and for on-the-go naps or when your little one is visiting grandparents, uncles and aunts, or any other caregiver, really.

Can you use white noise all day for babies?

As with swaddling, white noise isn’t meant to be used 24 hours a day. That’s because you want to give your baby’s ears and brain a break for several hours—every day—to learn the normal sounds of your home and your voice. So, save the white noise for calming your baby’s fussies and to improve naps and nighttime sleep.

How loud should white noise be?

The best volume for white noise depends if your little one is upset or not. If your baby is calm, your white noise machine should be set to between about 55 decibels (the level of a whisper) and about 70 decibels (the level of singing a lullaby). At that level sound can be safely played all night. When your baby is crying, you need to turn the volume up to nearly match the intensity of the tears in order to turn on their calming reflex. While a baby's cry can reach at 100 to 120 decibels, adjusting your white noise machine to be about  85 decibels should do the trick. (For some sound perspective, know that the sound inside the womb can reach over 90 decibels.)

While the decibel scale can be confusing, SNOO is not! SNOO is the only white noise device specifically designed to give your baby the exact level of sound they need, at the exact time they need it. SNOO quietly shushes all night between roughly 55 and 70 decibels (you choose), and when your baby cries, the sound increases no more than 85 decibels for just a few minutes. SNOO isn't the only "smart" white noise machine, though: SNOObear’s white noise shuts off after 30 or 60 minutes—and turns back on again if it "hears" your little one fuss.

When should white noise for babies stop?

There’s no need to turn off the white noise! For years, many parents continue using white noise with their children (and themselves) to boost sleep, and there’s absolutely no harm in that. But no worries if you want to stop. It’s super simple to wean from white noise whenever you want. Simply gradually lower the sound, bit by bit, over a week or two until it’s finally off.

There’s so much more to learn about white noise! Here are some of our most popular posts on this important sleep topic:

About Dr. Harvey Karp

Dr. Harvey Karp, one of America’s most trusted pediatricians, is the founder of Happiest Baby and the inventor of the groundbreaking SNOO Smart Sleeper. After years of treating patients in Los Angeles, Dr. Karp vaulted to global prominence with the release of the bestselling Happiest Baby on the Block and Happiest Toddler on the Block. His celebrated books and videos have since become standard pediatric practice, translated into more than 20 languages and have helped millions of parents. Dr. Karp’s landmark methods, including the 5 S’s for soothing babies, guide parents to understand and nurture their children and relieve stressful issues, like new-parent exhaustion, infant crying, and toddler tantrums.

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Disclaimer: The information on our site is NOT medical advice for any specific person or condition. It is only meant as general information. If you have any medical questions and concerns about your child or yourself, please contact your health provider.