This article is a part of CNN Underscored’s Guide to Sleep, a week-long focus on everything you need to sleep better. We’ll be featuring new products and exclusive deals all week, so check in every morning to see what’s new.

Noise can affect sleep for better or worse. White noise machines that emit just that — consistent noise — fall squarely in the “better” category. Constant white noise, like the kind produced by a white noise machine, has been shown to improve sleep quality because it helps mask sudden bursts of noise that may help some people more easily fall and stay asleep.

“White noise machine” is a blanket term that consists of basic machines that do the bare minimum (that is, emit white noise at varying volumes) to high-end pieces of tech that feature lights, automations and more. We tested 12 top-rated white noise machines (and four white noise apps), aiming for solutions with a variety of sound options and great volume control for heavy and light sleepers alike. After several months, four stood above the rest:

Best white noise machine overall

The Sound+Sleep Mini white noise machine contains 48 different sounds like rain, brooks, fans, ocean sounds and white noise. The other devices we tested feature some of these sounds, but the Mini is one of the only ones that has them all.

Best upgrade white noise machine

While our overall pick is a classic sound machine, the Hatch Restore white noise machine packs extra features like a color-changing light on the front, a digital clock display and routines to help you wind down and fall asleep easier.

Best white noise app overall

We liked the White Noise app for its ease of use, handy timers and alarms, and large selection of various types of sounds. You can download additional sounds in its marketplaces.

Best upgrade white noise app

The Calm app offers white noise and other sounds, and also meditation and breathing exercises, daily movement videos, music, motivational talks and tons of sleep options. The app also offers a free trial period.

If you’re looking for a plethora of sounds to soothe you into sleep, the Sound+Sleep Mini will fit the bill with more than 48 tracks across 12 categories that range from the standard (white and pink noise) to the environmental (rain or ocean).

It would be a lot to list out 48 individual sounds, but here are a few highlights: Fireplace inspired the same warm, cozy vibe you get from a nearby crackling fireplace. Crickets with light rain filled the space with a medley of natural sounds, transporting us to a relaxing night outdoors (without any of the actual bugs and rain). All of the soundscapes under the “Crowd” category reminded us of when we could go out to a café with a laptop. With such an array of sounds — more than any other we tested — it prevented the mundanity that we experienced hearing the same sounds over and over with most of the other machines.

Speaking of mundanity, some sound machines, such as the SoundSpa Portable and the Hatch Restore, have somewhat short soundtracks where you can recognize where the loop restarts. Sometimes hearing that tiny glitch when a soundscape has restarted made it more difficult for us to relax. With the Sound+Sleep Mini, we never recognized those repeats.

Of course, if you can’t set the volume just right, you’ll be adjusting it all night. And few devices offered as many gradations between whisper quiet and booming loud as the Mini. You can thank the high-fidelity 2.5-inch speakers for the latter. It’s not necessarily room-filling, but it does pack a punch on the audio scale and can sound bigger than it appears — helping to better mask ambient noises that could disturb sleep. The Sound+Sleep Mini features an upfiring speaker on the top, so it’s directionally pushing the sound upward. Thanks to its comparatively wider volume gradient, we were easily able to pick out a precise volume that we preferred.

The device also features an adaptive sound mode, wherein a built-in microphone detects environmental sounds and increases the volume in an attempt to cover them up. We tested this by clapping near the machine, then farther away and finally while having people converse loudly in the next room. We only noticed a significant volume change when the sounds originated in the same room as the machine. So if you have a noisy roommate, it could help, but with loud neighbors, you may have to change the volume yourself.

The sound quality is decent. The Mini is more than capable of reaching high and low notes, which greatly helped our immersion once we closed our eyes and listened to each track. It handled the tracks better than most of the others we tested, and there wasn’t a tinny quality to the sound, even when the pitches rose. Still, the Hatch Restore, which is nearly double the price, bested the Sound+Sleep Mini in this regard. The sound it puts out has more depth, and is produced with a much higher level of clarity, whereas the Sound+Sleep Mini is less crisp overall.

The Sound+Sleep Mini, as the name may suggest, is a compact device, with an asymmetrical teardrop shape and a flat top upon which the speaker resides. Like most of the sound machines we tested, it’s a cinch to set up. All you have to do is plug the included power cable into the bottom of the Mini, then plug that into the wall. Alternatively, you can insert 4 AA batteries beneath a bottom panel.

The device’s controls are laid over a flat surface on the side. They may look complex, but they’re not. A central circular button cycles through each category, while another button, labeled “selection,” controls which track is playing within that category. LED lights inside this panel intuitively indicate exactly which selection is currently playing. There’s even a snooze timer with 30-, 60- and 90-minute options. This particular timer is unique, lowering the volume gradually as it nears its end. It’s not a feature we often noticed, as we were asleep before it kicked in. The LED lights fade out too, so as not to distract you — although, they didn’t distract us at their full brightness either.

On the side near the controls are two audio ports: one is for audio input if you want to use the Mini as a speaker; the other is a headphone jack, a feature we wish more machines included. Using this option, you can become even more immersed in your selection of choice. The sound quality is even a little better with headphones on if you have a half-decent pair.

Overall, the Sound+Sleep Mini has everything you’d want in a sound machine. It comes with a multitude of soundtracks, expansive volume control and a timer for dozing off. In terms of design, it’s a sleek piece that will go well on your nightstand with controls that you’ll learn in a flash. At $64.95, it isn’t the cheapest option out there, but its multitude of features can appease any sleeper.

Boasting a companion app, class-leading soundscapes, routines that help you fall asleep and wake up easier, along with several lighting options (to, again, lull you to sleep or gently wake you up), the Hatch Restore is the ultimate sleep gadget. It also comes at a premium price: $129.99. But when you put all its functionalities together, that cost is justified.

We were blown away by the Restore’s 31 sound choices, consisting of soundscapes, music and narrated selections for meditation and rest. The tracks are high-quality in both fidelity and composition. Ocean Sounds in Maine, for example, consists of waves that you can hear splashing underfoot, with overtones of oceanic bird calls and an implacable yet soothing hum. If you close your eyes, then any one of the Restore’s soundscapes can whisk you away to another place. Even better, the tracks were long enough for us to fall asleep to before they ended and started over the loop, lasting longer than those of any other machine we tested. Oceans of Maine is a whopping 45 minutes in duration.

And while its maximum volume is a smidge lower than that of the Sound+Sleep Mini, the volume control is even more precise with 100 levels of volume to choose from, which is easily adjusted in the app or on the side of the device.

The Hatch Restore has a very pleasing design, resembling a semicircular dome with a woven strip along the bottom to house an LED dot display and a sizable light above. Then there’s the large light on the front of the Hatch Restore. Using the companion app, you can change this light to any color or brightness you want. You can go for a bright light for reading before bed, a dull warm light to simulate a sunrise or anywhere in between. The color can’t be controlled on-device (only through the app), but the brightness can.

In addition to sounds of rain, waterfalls, whale calls and other beautiful soundscapes, you can also select relaxing music and narrations. The music is primarily composed to induce feelings, and the tracks are named accordingly. Acceptance contains hopeful string instruments and synth notes, making you feel like you’re floating on a cloud. A Stormy Cabin, on the other hand, has a lower, more somber tone with a deep violin. The narrated segments have mindfulness training on being aware of your breathing and muscles as well as techniques for clearing your head after the day and many more options. You can even listen to stories, such as readings from famous novels or calming tales about fictional events. We, for one, enjoyed one about taking a vacation to a warmer place; it helped us escape the winter under some cozy sheets.

To tie it all together, there are what the app calls Routines. These are customizable sequences that can be activated with a tap or scheduled for a specific time. For example, we relied on a built-in sequence called Bedtime to relax us before bedtime. With that, when you tap a touch control on the top of the Restore, a warm white light comes on for reading. When you tap it again, a 10-minute track called Meeting Sleep With Ease plays, wherein a narrator helps you calm your mind with visualization meditation before bed. Lastly, a track called Light Rain rings out with the pitter-patter of rain until you tap again the next morning, or until your morning routine begins. You can have any number of steps happen in any order you’d like for as long as you’d like. And you can schedule them to occur on specific days of the week too. It’s a feature that we found endlessly useful, helping us keep our sleep regular and allowing us to wake up feeling refreshed.

We loved the ability to control all of this — from volume to the light color to soundscapes — through the app. But there is a catch: You only get six months of the app for free, after which you’ll have to add $49.99 annually (or $4.99 monthly) on to the already high price tag to keep the full library of ever-changing sounds and features. If you opt not to subscribe, you’ll keep fewer than 10 free options, so your library will be greatly limited.

The Hatch Restore truly modernizes the sound machine, with excellent sound quality, a customizable light, a digital clock and an app that upgrades the experience. The only setback is the $129.99 price tag. However, we think you get what you pay for — and more — with the Hatch Restore.

If you’re looking for an app that has a large selection of sounds and is easy to use, we liked the White Noise app. It has a variety of different color noises, including white, pink and brown. It also has varying water sounds, from light rain to extreme rain, campfires and different fans like box, oscillating or bathroom. We also liked that we couldn’t tell where the loop is in the sounds we tried, so there’s no sound disruption.

The app also lets you set timers to stop sounds and set alarms to wake up in the morning. While it doesn’t include meditation features like some of the other apps we tried, it does offer quite a bit for a white noise app that costs $.99. It has over 50 sounds that you can listen to individually or mix together, and if that isn’t enough, you can also download additional sounds in its marketplaces.

Unlike some other white noise apps, the Calm app offers more than just white noise and soundscapes. According to Calm, its goal is to “help you improve your health and happiness.” The app offers meditation, breathing exercises, daily movement videos, music for work, motivational and mindset talks, a section for kids and a ton of sleep options.

The options for color noises are limited to white and pink noise, but there are numerous other sleep options, including sleep stories, nature sounds, sleep soundscapes, relaxing music and sleep meditations. There are also celebrities narrating sleep stories, including Harry Styles, Black Pink’s Rosé, Matthew McConaughey, LeBron James and more.

Calm and Headspace are extremely similar, both in terms of offerings and price. However, Calm edged out Headspace since Calm was the only one that had white and pink noise. It also worked equally well on an iPhone and Samsung phone, whereas Headspace had trouble on the Samsung.

What is white noise? White noise is a type of noise that contains noise of all frequencies equally and sounds similar to static. Because it contains all frequencies, it is said that it will mask out other sounds, which is where white noise machines come in.

How white noise works. Rather than being woken up by a noisy neighbor or partner snoring, white noise machines are able to mask sudden noises with its continuous sound so you’re not suddenly jolted awake and you stay asleep. If you’ve ever had a friend who swears they can only sleep with a fan on, it’s the same concept as white noise: that the continuous sound of the fan can mask other sounds. This lull of constant noise may also help you fall asleep.

Not for everyone. That being said, white noise machines may not work for everyone. Some may find the sound of white noise irritating, which is why you’ll often find other sound options with white noise machines. Also keep in mind, some may find white noise machines work well, some may prefer other soundscapes and some may need total silence. It varies person to person and may take some experimenting to find which noises, if any, work for you.

Try different color noises. For some, white noise may sound irritating rather than soothing. If that’s the case, then you may want to experiment with different color noises, such as pink or brown, which sound deeper than white noise. It may take some experimenting to find which color noise works best for you.

Variety of sound. If you already know your preferred sleeping sound, then you may want to purchase a machine that has only that specific sound or just a few sounds. This way, you’re not scrolling through endless options to get to your favorite sound. However, if you’re new to sleeping with white noise, then consider purchasing a device with numerous options so you can figure out which works best for you. While white noise is a popular option, not everyone finds they can sleep with it; you may want to try different soundscapes instead.

White noise apps. If you’re unsure about sleeping with white noise or don’t want to invest in a device just yet, then apps are a good place to start. Many offer an assortment of sounds and are low cost compared to white noise machines. Just keep in mind that the sound quality is only as good as your phone’s speaker, and you may need to keep your phone charging at night since it will drain the battery.

To really get a grip on each machine’s capabilities, we took notes on setup, listened to every soundtrack, pressed every button and control, examined the overall design, noted and tested additional features and researched warranties. We then compared and contrasted these features to find the best of the best.

Naturally, our first step was setup. Out of the box, we wanted to know just how easy or hard it was to get each machine up and running. This included cable management, battery insertion and setting up apps.

Once the devices were operating, we dove into our sound options category. Variety was important to us — how many unique sounds can each sound machine make, and how many categories were there? As we listened, we also noted sound quality. Does the sound come out fuzzy or clear? And how much tonal range does each device have? Realistic-sounding bird calls, for example, require a lot of higher pitches, whereas a thunderstorm takes deep notes to reproduce. Finally, volume control was a big factor for us. The more volume options the better.

On top of sound quality, a lot of the devices we tested had additional features. A standard we looked for was a snooze timer so you can set your device to eventually turn off. But any functional extra features like lights, fans or headphone jacks were deemed to enhance the user experience and thus improved a device’s score.

Design and controls were our final categories. It’s important for a sound machine to have understandable controls, especially if you may be drowsy during a lot of its use. Most devices had on-unit controls in the form of buttons or touch sensors. We looked at these controls — where they were placed, how they were labeled and how numerous they were — to determine whether they were intuitive or cluttered and hard to understand. Design wasn’t a huge category, but we still considered the visual aesthetic and size of each sound machine. In general, a sleeker, more modern design caught our eyes, which most of the devices fulfilled. The real kicker was size — a big, clunky sound machine that will hardly fit on your nightstand scored fewer points here.

Last but not least, we researched the warranty of each device, be it on an included pamphlet or from the respective company’s website.

The Honeywell Dreamweaver isn’t strictly a sound machine, but instead it’s a fan. Still, we included it because many sound machines feature tracks meant to simulate fans. The Dreamweaver is a cylinder with a vent on the side; it’s about the size of a gallon of milk.

The device has three fan strengths, a timer and an oscillating mode. Naturally, since it doesn’t have to simulate a fan, it’s great for people who enjoy that sound. If you’re not interested in the breeze that comes from the vent on the side, then you can close it. It’s a nice machine, but it doesn’t feature as many sounds as other devices we tried.

The Lectrofan is another one for fans … of fans! This small, octagon-shaped device produces 18 different sounds, half of which are the sounds of various fans and vents. The other half are colored noises like white noise, pink noise and brown noise. These color labels just indicate the range of tones that each noise contains.

The sound quality is on the higher end, but otherwise, this sound machine is rather simple compared to the Hatch Restore. Plus, the Sound+Sleep Mini has more categories and total options, including both colored noise options and fan sounds, so the Lectrofan falls short there too.

The Lectrofan Micro 2 is another fan-themed device but with a twist. The cylindrical Micro 2 fits in the palm of your hand and comes with colored noise, fan sounds and ocean audio, totaling 11 built-in sounds. It also has a nifty swiveling speaker on the top that can be turned to point in any direction. Then there’s the twist: The Micro 2 doubles as a Bluetooth speaker. Thus, it has the potential to play any sound or music you can find.

That being said, you’d have to track those down on your own and keep your phone on all night for the speaker to function that way. Though the sound quality is great and the Micro 2 is the most compact device out of those we tested, it doesn’t functionally compare to our winners.

The SoundSpa Portable is the definition of a basic sound machine. It’s about the size of a clock radio but more circular and recumbent in shape. In a ring around the central speaker are the lone six sound options: summer night, thunder, brook, ocean, white noise and rain.

The Sound+Sleep Mini leaves this selection in the dust, and features better sound quality too. Fortunately, the SoundSpa at least has a few timer settings and a precise volume knob. There really isn’t much more to say about it. It’s definitely one of the cheapest options out there if you are going for a bare-bones sound machine.

The Hatch Baby Rest comes from the same family as the Hatch Restore. This sound machine is a tapered cylinder that primarily serves as a light and uses the Hatch Sleep app for control. This lets you change the color of the light as well as the sound that’s playing. You can also schedule alarms and bedtimes with it. Though it’s advertised toward babies and toddlers, adults can certainly get use out of it too, save for the fact that several of the 11 sounds on the app are gentle music and lullabies.

Like the Restore, you can operate it by touch, except it has button controls hidden on the bottom too. The Baby Rest resides in an awkward middle ground between the Sound+Sleep Mini and the Hatch Restore, both of which offer far more sound options.

The Yogasleep Dohm Classic was our least favorite sound machine. It has a plain cylindrical shape and a switch on the back that controls its internal fan. The fan has two power settings, and the actual sound comes from a series of slots on the side and top of the machine. By twisting the body of the device (an admittedly cool control scheme), you open more of these slots and can change the volume of the sound. However, that’s all there is to this machine. If you like fan sounds, then it’s a decent choice. But it doesn’t provide as strong of a breeze or as many strength options as the Honeywell Dreamweaver.

Yogasleep Dreamcenter Mini Multi-Sound

$30 at Amazon

We found this sleep machine easy to use, with intuitive illustrated buttons and almost no need to read the instruction manual to learn how to use it. It has 26 sleep tracks, including nine white noise options, 10 sleep songs and seven nature sounds and fan sounds. The sleep songs also include lullabies, plus the device has a night light, so this would work well for a kid’s room. However, it also has a headphone jack for those who sleep with a partner who does not also want to listen to the sleep sounds.

We found the sound quality muffled compared to some other machines, but it may be preferable for those who like a low pitch to their sound. But it was so muffled that it was a deal breaker for us. At its current price, it’s one of the better deals on this list for the variety of noises available and its 25-setting volume range. It also has a sleep timer with 45- or 90-minute shutoff as well as an eight-hour option. This timer feature is handy for those who do not like to sleep with noise all night or who want it to shut off after a full eight hours.

In addition to having white noise, this device also has a few meditation features. There’s a guided breathing soundtrack that has a soft voice that gently tells you to breathe in, hold and breathe out. After a few rounds, the voice fades off, leaving you with the sounds of a soft inhaling and exhaling sound to guide you on your own. We found it to be very relaxing to use on occasion. But if you’re looking for a lot of meditation options, then you’re better off going with one of the apps like Calm or Headspace.

There are also two other melodies that, according to iHome, mimic brainwaves. The “Zen” tonal melody is said to mimic Delta brainwaves of a mind in meditation or healing sleep. The “Dream” sound supposedly mimics the theta brainwaves of a mind in dreaming REM sleep. While we didn’t measure the brainwave activity while listening to the sounds, the sounds did lull us into a pleasant afternoon nap.

In addition to these soundtracks, it also has ocean, storm, nature, brown noise, pink noise, white noise, white noise combined with melodies and heartbeat sounds. We found the sound quality was crisp and, because the whole device is a speaker, it sounds more like it’s filling the room compared to some other devices. It doesn’t get as loud as some other devices, so this is best for someone who sleeps next to or close to their device. It can also run on four AA batteries for portability, and it’s lightweight if you want to travel with it.

$60 at Ulta

With this machine, you get a sunrise alarm clock and white noise machine in one. We found it was easy to set up and program different functions such as “Wake to Sunrise,” but we did need to refer to the instruction manual in order to program it, which was clear and easy to follow.

It comes with 15 soundtracks, including nature sounds like ocean waves and storms as well as relaxing music. It’s confusing which sound is white noise since the brand gives its sounds names like “Zen,” “Air,” “Drive,” etc., and it’s not listed in the instruction manual if any are white noise. We found the “Quiet” sound was most similar to white noise.

We liked that the clock has an auto-dim feature that changes with the brightness of the room so it’s not glaring in your face while you’re trying to get to sleep. The brightness level is also adjustable and there’s an option to turn the clock off altogether. You can program the device to wake to sunrise and wake to sound.

The one downside, for those who like to leave sound on all night, was that the
Wake to Sunrise feature turns the sound off when it starts, which can be jarring if you’re still sleeping. However, this sunrise alarm clock is about half the price of other sunrise alarm clocks with more features, so it may be worth it if that doesn’t bother you.

The Brookstone Sleep Sound Mixer does not technically have a white noise option, so it’s best for those who like to sleep to nature sounds or for someone who will use this while working in their office for background noise. There are eight sound options, including a fan that is lower-pitched and sounds similar to a box fan. The remaining sounds are ocean waves, rain, flute music, campfire, thunderstorm, crickets and birds.

It has a fun design that resembles a music mixer that a DJ would use, letting you mix all the sounds at varying volume levels. We loved that we could play DJ with our sounds and blend multiple sounds, unlike other white noise machines that allow for only one sound at a time. We liked the sound quality too; the only drawback is that the speaker is located at the bottom of the device, so, depending on what surface it’s set on, it sounds slightly different.

Headspace is equally geared toward meditation and sleep to help you relax during the day and sleep better at night. It has abundant choices for both sleep and meditation, so if you like variety, it will be hard to run out of choices with this app.

It has four main categories: meditation, sleep, focus and move, which includes guided yoga, dance and cardio workouts. Within the sleep category, there are plenty of options for sleep sounds, such as music, stories, “sleepcasts” (think sleep music and podcast in one) and typical soundscapes like jungle, forest and water sounds. There are even sleepcast options with celebrities like John Legend who’ll tell you a bedtime story.

There isn’t a plain white noise sound; when we searched for it in the app, other soundscapes came up like “warm engine” and “static with strings,” which have some white noise but are not solely white noise. If you’re looking for a white noise substitute in the app, then it may take some time to find one you like.

This app costs $69.99 per year or $12.99 per month, so it’s best for someone who will take advantage of all the features the app has to offer. If you’re unsure, it also offers a free seven-day or 14-day offer depending on which plan you choose. Samsung phone users may want to avoid this app, as we found it did not work well, taking a long time to buffer each sound on our Samsung Ultra 21 phone. However, it worked well on our iPhone.

The MyNoise app offers the most sound customization of the apps we tested. It comes with a set of eight noises, including white noise. Within each sound, there are sliding buttons to adjust the sound to your liking. Some soundtracks also have the ability to adjust the frequency and “color” of the sound, both of which can make the sound higher or lower pitched, depending on the option chosen. The app also offers different scenarios for some sounds like rain, which lets you choose options such as “distant storm,” “under porch” and more.

There are additional free sounds available and some that cost $.99 to download. There are also sounds that are only included in the “bundle-only” option, which costs $11.99 and includes all sounds. Unfortunately, we found that this app is not as intuitive or straightforward to use as others. Also, unlike most apps, swiping out of the app does not close it; it requires you to manually pause the soundtrack and then close out.