Your Ultimate Guide to the Best Color Noises for Sleep

Soothing sounds have lulled us to sleep for millenia. Long before the advent of earbuds, the gurgle of a babbling brook or chirp of crickets served as a natural soundscape, allowing our prehistoric ancestors to tune out and relax.

In 1667, Pope Clement IX, whose insomnia was improved by sleeping to the sound of a fountain, commissioned architect and sculptor Gian Lorenzo Bernini to invent the world’s first sound machine for use in his bedroom. The resulting device — a wheel that struck paper globes, creating a pleasant sound — was about three centuries ahead of its time. The democratization of sound machines didn’t come until the 1960s, with the invention of the electronic Marpac Sleep-Mate sound conditioner (later known as the Dohm). All to say, humans have been trying to use sound to block disruptive noise and get better rest for quite some time.

Our ears never fully rest, making sound a direct line to the brain during sleep. And indeed, nighttime auditory stimulation has been shown to impact the brain in a number of ways. Research indicates that certain types of sound may be helpful for overnight memory consolidation, metabolism regulation, hormone release, immune function, and more.

Of course, not all sound is created equal, and researchers exploring the effect of sound on the body place stimuli into distinct noise categories. Binaural beats and 432 hz music, for example, are two modalities of high interest. But the most fundamental sound categories are known as “colors” of noise. Here, we’ll take a deeper look at the spectrum of sounds and how each one can impact sleep.

What is colored noise?

Most people are familiar with white noise — the hiss of an electric fan or buzz of TV static. And you may have also heard of pink, brown, or even green noise in recent years. If not, you likely consider those “white noise” too. But each color noise has a distinct sound that may come with its own distinct benefits.

The categorization of audible sounds by visible features can seem curious at first. A sound is a vibration perceived by the human ear. The number of times a sound wave passes in a second is known as its frequency and determines how the noise sounds to us — low- or high-pitched or somewhere in between. We can’t see the sound wave. It has no visible color. But the categorization of sounds by color comes from an analogy, common among audio engineers, between white noise, which technically contains all audible frequencies at an equal intensity, and white light, which contains all visible frequencies on the color spectrum.

Acoustically, brown noise is a random combination of all audible frequencies on the sound spectrum that emphasizes lower, deeper tones, corresponding to the deep red/brownish end of the ROYGBIV spectrum. Pink noise, which isn’t quite as deep and contains more mid-tones than brown noise, aligns with pink on the light spectrum. Green noise emphasizes the middle range and is also used to describe frequency response of a range of natural sounds. Blue and violet noise emphasize the upper end of the sound spectrum, turning down the low tones.

Who first made the color-light spectrum analogy isn’t well documented. But the color-noise terms are used across disciplines with a history going back to Edison and Einstein. Here’s a look at how we came to categorize background noises by color.

Exploring the different color noises for sleep

Researchers have only recently begun investigating the effects of color noises beyond white. White and pink noise are the most studied of the bunch so far. White noise’s ability to promote sleep and focus and pink noise’s ability to deepen sleep are now both fairly well established. And while research has also been conducted on memory, productivity, learning, and relief for tinnitus (ringing in the ears), evidence is still limited and the early results have been mixed. Few studies have looked at brown noise’s benefits, and none have examined the effects of green, blue, or violet noises. But color-noise enthusiasts regularly broadcast anecdotal evidence on social media. Let’s take a closer look at how the different color noises might compare for sleep and beyond.

Color Noise Type	Explanation	Benefits	Best For
White Noise	A continuous noise mixing all audible frequencies at equal intensity and at random	White noise is the color best at masking a wide variety of external sounds, because it covers the whole acoustic spectrum equally. Research has also shown it may help some people fall asleep faster, stay asleep longer, focus better, remember more, learn new words, focus (with ADHD and without it), and relieve tinnitus.	Anyone living in urban areas or with noisy neighbors, people with insomnia, partners of any kind of snorer (i.e., from a whistly high pitch down to a low drone), parents of babies and small kids, open-plan office workers, students, people with ADHD, people with tinnitus
Pink Noise	A continuous noise mixing all audible frequencies at random but emphasizing middle and low tones over high ones. Pink noise sounds lower and deeper than white noise but not as deep as brown.	Pink noise has been shown to deepen sleep, increase the time spent in deep sleep, and boost memory consolidation. By deepening sleep, pink noise may also promote its benefits like metabolism regulation, hormone release, and immune function. Pink noise may also help some people find relief from tinnitus and fall asleep faster by masking middle and lower tone noises (think traffic, music, speech, cooking).	Light sleepers who frequently wake overnight, anyone who wants to improve memory, partners of middle to-low-tone snorers, people with tinnitus
Brown Noise	A continuous noise mixing all audible frequencies at random but emphasizing lower and deeper tones over middle and high ones. This is the deepest, lowest color noise.	Research is limited, but like other color noises, brown noise may help you sleep better by masking disruptive low-tone noises in your environment like rumbling traffic, construction noise, and bass thumps from neighbors’ music. Similarly, brown noise may block distracting sounds around you during the day to boost work performance and concentration. It’s also possible that like white noise, brown noise may be able to improve some ADHD symptoms, but no research exists to support the anecdotal claims.	Partners of deep-tone snorers, anyone whose neighbors are doing construction, open-plan office workers, remote workers in coffee shops or any public space
Green Noise	A continuous and random variant of white noise, dampened at both ends of the spectrum, emphasizing middle frequencies, reminiscent of nature sounds	Researchers haven’t studied green noise, but they’ve shown nature sounds can reduce anxiety and help people relax, which may explain social media claims that green noise (which has a similar tone) helps some people fall asleep. Like other color noises, it may be that green noise helps you fall asleep faster and stay asleep longer by masking disruptive middle-range noises (like adult voices, traffic, cooking) in your environment, but this hasn’t been studied.	People who enjoy relaxing to nature sounds, people with talkative neighbors or housemates, partners of middle-range snorers
Blue Noise	A continuous noise mixing all audible frequencies at random but emphasizing middle and high tones over low ones	Blue noise’s higher pitch effectively masks mid and higher pitch sounds in your environment like children’s voices, a small tinny speaker, or AC noise. And though researchers haven’t studied it, some people say it helps them focus, relax, and sleep. Others say it blocks the ringing in ears of tinnitus sufferers.	People who need to block the sound of children’s voices, anyone who wants to mask the sound of flute or violin practice, partners of higher pitch snorers, people with tinnitus *We don’t currently recommend using this noise. It is unstudied and unpleasant to most human ears.
Violet Noise	A continuous noise mixing all audible frequencies at random but emphasizing higher tones over middle and low ones	Violet noise’s high pitch can mask upper-frequency sounds in your environment like children’s squeals, keyboard clicking, high AC sound, and fan noise. Though violet noise hasn’t been researched, people make similar claims about it on social media, saying it helps them focus, relax, and sleep or block out the ringing of tinnitus.	People who need to block the sound of squealing children, anyone who wants to mask the sound of flute or violin practice, partners of high-pitch whistly snorers, people with tinnitus *We don’t currently recommend using this noise for sleep. It is unstudied and unpleasant to most human ears.

What color noise is best for optimal sleep?

There’s no single best color noise for optimal sleep. Which sound works best for you may depend on your individual sleep challenges, circumstances, and preferences. For example, if external noise disrupts your sleep, colored noise can effectively mask it. But the most effective color partly depends on the type of sound that is disrupting you. A sound best blocks other sounds whose acoustic frequencies closely match it. “White noise is equal spectrum everywhere,” says Robert M. Thomas, composer, sound designer, and NextSense’s Functional Audio Consultant. “So it’s kind of masking everything in the same way.” That makes white noise a good go-to—unless, of course, the sound of white noise is grating to your ears.

How to try different color noises for sleep

There are many ways to try different color noises for sleep, from traditional sound machines and apps to smart speakers and earbuds. One caveat with apps or streaming services: “A lot of the sound files on YouTube and Spotify are not correctly labeled,” says Dan Berlau, PhD, professor of pharmaceutical sciences at Regis University. “I have seen white noise labeled as brown noise, brown noise labeled as pink noise, and every possible other combination.” You can avoid that kind of confusion with a dedicated sound machine or another product with vetted soundscapes, such as Tone. If you aren’t sure which type of sound works best for you, take these steps to experiment and find out.

Taking your individual sleep challenges into account, refer to the table above and consider which sounds may be a fit for you. Then give them a listen to see which variation most appeals to your ears. Still unsure? “I believe a good starting point would be to try listening to brown noise for a few nights and see if it helps,” Berlau says. “Brown noise is much more pleasant to listen to [than white noise] for many.”
Sleep journals are considered an important tool by sleep medicine doctors. Try keeping one to track which sounds best aid quality sleep for you. Here’s a sleep journal you can download and try, using the bottom row to note which colored noise you used and any other relevant details about tracks or volume.
Speaking of volume, more isn’t necessarily more effective. For one, you want to protect your hearing. “Below 70 dB is the recommended level for general no-harm listening,” Thomas says. “But for sleep it would be much more normal to use an acoustic stimuli down at the range of 30 to 40 dB.” The World Health Organization agrees. The maximum volume it recommends for good-quality sleep is less than 30 dB for continuous background noise (the equivalent of a whispered conversation) and 45 dB for individual disturbances (the equivalent of soft music).

The Tone Take: The best sounds for sleep? It’s personal

There’s a world of colored sounds to explore, and science continues to reveal how and why these noises affect sleep and well-being. In many cases, the best sound for sleep is the one you find most pleasant and relaxing. With a little bit of research and trial, more restful sleep is in your future.

A Guide to the Different Color Noises for Sleep

﻿Your Ultimate Guide to the Best Color Noises for Sleep