How to Choose the Best Baby Monitor for You

Buying Advice
By ⋅ Review Editor, BabyGearLab - Thursday November 15, 2012

Buying a baby monitor can be complex due to the large number of products available. It is especially complicated for the first-time parent, since it isn't obvious what to look for in terms of features, and what pitfalls to avoid. In this article, and our corresponding review of baby monitors, we have attempted to share our findings and learnings.

Price is one of the clear differences between the monitors on the market. While low-cost options are abundant, our tests show dramatic and very pragmatic differences between low-cost baby monitors and higher-end monitors. Key differences exist in the ability to receive a clear signal over distance and through walls, as well as the ability to avoid interference from the neighbors monitors and your other wireless devices. More subtle differences exist in features such as sound sensitivity.

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We tested 20 of the most popular and highest rated baby monitors to see which was the best. The award winners are shown front and center.
Credit: BabyGearLab Staff
Disturbingly, we found no correlation between manufacturers' claims regarding a monitor's range, with what we actually observed in our extensive hands-on testing. You would expect a monitor advertising 2,000 foot range would work at a longer distance than one advertising 1,000 foot range — but this did not turn out to be true in our tests. We advise you to view manufacturer's range claims with great skepticism.

In this article, we'll take you through the different types of monitors, what features to be on the look-out for, and why.

Which Type of Baby Monitor? Video? Sound? Movement?
We consider the essential benefit of a baby monitor is to allow you to sleep more and better, by gaining confidence that the monitor will awaken you if baby needs attention.

Why Sound Monitoring Is the Most Important
In practical use, it is the sound capability of the monitor that you'll most rely on. A newborn will typically cry to alert you to their need to nurse and diaper change every 2-3 hours, providing you a brief window to sleep in between. As baby gets older, the time period will increase and by 6 months you might enjoy 4-6 hour periods of sleep before baby crys.

The more confident you are in your baby monitor's ability to awaken you if baby needs attention, the better you'll sleep. This is especially important for first-time parents who tend to be more anxious, and thus more sleep deprived than veterans.

We recommend that you emphasize sound monitoring capabilities in your purchase decision.

Why Video Monitors Can Get You More Sleep
Video plays no role in the essential act of alerting you to baby's crying, and to address that video monitors usually include sound monitoring as well.

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Night time video display uses infrared LED to light baby.
Credit: BabyGearLab Staff
However, video can play a key role in helping you determine whether to make an immediate trip to check on baby. Sometimes baby just wakes up briefly and then self-soothes back to sleep. The ability to look in on baby, and see what is going on in the crib, can be very helpful to make sure nothing serious is going on. For this reason, we loved the ability of the Motorola Video monitor and most others to pan and zoom under control of the parent unit.

A video monitor is also useful if you have multiple children, and want to keep an eye on two areas at the same time. After baby is older, a video monitor can be useful to watch over kids playing while you do chores like laundry or things in the kitchen.

For the full scoop on video monitors, take a look at The Best Video Monitor Review and its companion article How to Pick the Best Video Monitor.

Why Movement Monitors Are Controversial, Yet Might Save Lives
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Angelcare Movement & Sound (AC401 Deluxe Plus). Front views of baby unit (left), parent unit (right), and sensor pad (background).
Credit: BabyGearLab Staff
A new parent can't help but contemplate the worst case scenarios: what if baby stops breathing? A few monitors go beyond just sound and video, to attempt to alert you in the unlikely event that baby stops moving. The Angelcare Deluxe is one such monitor. The way it works is that a movement sensing pad is placed under the crib mattress. The detection pad is sensitive enough to notice the small movements a baby normally makes when sleeping. If the movement stops, the Angelcare sounds an alarm after a 20 second delay. Getting the pad to work properly requires testing, tuning the sensitivity so that vibration such as from your heating or AC don't fool the monitor, and installation of a firm board under the mattress.

The idea of an alarm that will sound if baby stops breathing is particularly interesting to parents in the first 6 month period where the risk of Sudden Infant Death Syndrome (SIDS) and other sleep-related death causes are most significant.

So, what's the controversy?

There appears to be no scientific study available that validates that monitors such as the Angelcare actually reduce the risk of SIDS or sleep-related infant death. These are not medical-grade monitors, and their effectiveness is questionable.

Moreover, both the American Academy of Pediatrics and the National Institute of Health have come out with formal policy statements recommending that parents do not buy products which claim to reduce the risk of SIDS, citing the lack of data to indicate such products work.

In contrast, there is a published set of techniques advocated by AAP and NIH that have been proven to reduce the risk of SIDS and sleep-related death. It would be a grave mistake to ignore these proven techniques to reduce the risk of SIDS and sleep-related death, because you had false confidence in your baby monitor.

So, what does Angelcare have to say about all this?

Not much, at least not in their documentation or website.

Angelcare seems to ignore the obvious question about their product's benefits or effectiveness. In our examination of their product packaging, marketing materials, and the FAQ section of their website, we found no mention of SIDS or sleep-related death. They do not claim their product will alarm if baby stops breathing. In fact, as far as we can tell they fail to make any benefit claim regarding their movement monitors other than to claim that the monitor will alarm if no movement is detected and that their monitors offer "peace of mind" to parents.

In the end, Angelcare leaves the question of whether their movement detection feature might save a baby's life unanswered.

In the favor of Angelcare's products, are a handful of passionate and compelling testimonials in user-reviews that describe cases where the Angelcare movement monitor did alarm in situations where baby had stopped breathing. In those cases, the alarm allowed those parents to revive their baby, and appears to have been instrumental in saving those babies lives. Critics say that those cases were probably not SIDS as formally defined medically, but rather a case where baby stopped breathing from asphyxiation or other sleep-related causes. From our point of view, we don't feel the semantics matter. The Angelcare alarm appeared to have worked in those cases to save lives, and we think that is significant.

Our take on it has been to evaluate the Angelcare product's primarily on their sound monitor capabilities and other features, and to simply consider the movement detection feature as an added bonus — albeit one we like, as it seems to be one more thing that might help alert parents to a potentially dangerous situation.

We urge you to read and follow the American Academy of Pediatrics guidelines on:

One Parent Unit or Two?
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Two parent units can eliminate the hassle of constantly moving both monitor and power supply as you move from master bedroom to other rooms.
Credit: BabyGearLab Staff
Many parents get by using just one monitor, placing the power supply in their bedroom (the main location you'll use your baby monitor) and taking the parent unit with them to the kitchen and other rooms in the house. This works just fine and is only a minor hassle so long as you're monitor's battery life is sufficient. But before the time your baby is a year old you'll probably find that the battery life on the rechargeable parent unit has degraded to a fraction of it's initial longevity. You can solve this by replacing the rechargeable batteris or by simply moving the power supply around with you.

Or, just get a two parent unit baby monitor and you'll eliminate a lot of that hassle.

The most convenient way to use a baby monitor is to have a two-parent unit model so you aren't constantly having to move the baby monitor from one location to another. Dedicate one parent unit in the master bedroom and plug it into the wall. You generally won't be moving the unit that is in the master bedroom. Place the other parent-unit in the kitchen or living area where you'll be while baby is sleeping in the day. You will often move this 2nd monitor around as you move from the kitchen to another room to work or watch TV, etc. Place the power supply for the 2nd monitor wherever you'll use it most (the kitchen usually), and use it on batteries when in the other room(s).

However, some of the higher-end monitors, such as the Philips Avent DECT, and the video monitors often do not have a 2nd parent unit available (video monitors often have the option of a second camera, but not typically a 2nd parent unit). As a result, with these monitors you'll be forced to run them on batteries or drag around the power supply when you are out of your maaster bedroom.

Range, Clarity, and Interference
Range, clarity, and interference are all interrelated. A monitor that offers good range can be brought to it's knees by interference from another monitor or electronic device on the same frequency. Similarly, the clarity of sound deteriorates as you increase the distance. That said, there are substantial differences between devices.

Range
Most manufacturers state a "range" for their monitor in their marketing materials and on their packaging. The stated range will be a so-called "open field" range test performed where there are no obstructions between the baby nursery unit and the parent unit. These "open field" range specifications are very misleading for several reasons. First, you aren't going to use your baby monitor in an open field, you'll use it indoors with walls between you and baby. Who cares if the monitor can allegedly transmit 1,000 feet across an open field? Second, we found no correlation between the stated ranges from manufacturers and what we measured in our own extensive range tests. Third, we found surprisingly little correlation between even our own "open field" range tests and our "indoor" range tests; a monitor that went twice as far as another in open field tests, might not offer any better performance indoors.

For example, we found that the monitors which claimed the longest range of 2,000 feet in their advertising (more than 2x the nearest competitor), performed worse in both our open field and indoor range tests than many other monitors which boasted half or less that range.

Bottom line: don't trust the manufacturer's range distances. They are flat out misleading.

Your actual range at home is what matters and that is going to be very different than the manufacturer's stated range in any event. Inside your home, where it really counts, the range is going to be anywhere from 5 to 30 times less than the open field range. Each home is a bit different since your home's walls and wiring will present unique obstructions that interfere with the monitor's ability to receive a clear signal. Further, each monitor is different and some are much better at getting a clear signal through multiple walls and distance than others.

So, how can you get a grip on the real range you can expect from a monitor?

We concluded that the only way we could find out was to perform our own tests, both indoors and open field.

Since our tests were done in a consistant manner across all the monitors we tested, we recommend you look closely at our test results to compare and contrast monitors and get a feeling for relative range performance. We also advise you to focus on our Indoor Range Test results primarily, since the open field range numbers are less predictive of what you'll find in your home.

Clarity
The clarity of a monitor refers to how clear the sound comes through from baby's room, or in the case of a video monitor, the video image quality as well as the sound quality.

It is not absolutely critical that you hear everything in baby's room crystal clearly. So long as you can hear baby cry, you've covered the basic functional need.

But, it sure is nice to be able to hear everything clearly. And, given two monitors that are otherwise identical in their performance, we'll take the one with better clarity every time (or pay a bit more to get it).

The downside of clarity is when static hiss is overwhelming the sound of baby's room. Some of the low-cost monitors are full of annoying hiss and static even when used in the room next door to baby. That kind of background noise can drive you nuts, and if the monitor lacks a sound activation feature to filter it out, it's going to wreak havoc on your ability to sleep.

We developed our clarity ratings by testing monitors in the room next door to the baby units, using an iPod sound loop so that all monitors were tested under identical conditions.

We also tested video image clarity in both daytime and nighttime conditions, using a color chart and an eye chart to help use discern visual clarity. One of the key areas where video image clarity comes into a play is the ability to see if baby's eyes are open. This requires both good image clarity and careful placement of the camera (you'll want the camera and any cords well out of reach of baby, placed high enough to look down on the crib).

Interference
Baby monitors suffer from two primary types of signal interference. One is the degradation of sound quality as the distance and number of walls is increased. As distance & number of walls is increased, the signal gets weaker and more background noise is evident. This is particularly noticable on the lower-cost monitors where the interference can reach intolerable levels with moderate indoor obstruction (>50 ft and 4 walls). The other common source of interference from other radio frequency devices such as other baby monitors (perhaps a neighbor's monitor) and/or wireless telephones. The higher end monitors, such as the Philips Avent DECT, seem impervious to this kind of interference in our tests, automatically finding a clear channel for communication. While not automatic like the Philips, we found changing the channels on the Angelcare monitors allowed us to effectively run two at the same time without cross-talk or interference. The Graco monitors were able to work with other monitors on, which is impressive considering their relatively low cost. On the other hand, all the monitors under $45 that we tested were very susceptible to interference from other baby monitors. If other monitors were turned on, we found the range of the lower cost monitors plummeted to less than half, and the level of static was substantial. Tuning to different channels did not seem to help significantly.

Save Your Receipt and Return Any Monitor with Interference Issues
The interference issue is significant enough that we encourage you to buy your baby monitor only from a retailer that allows you to return the product for exchange or refund in the event you have an interference problem. This is particularly important with the lower cost monitors, such as the Sony Baby Call and other monitors costing less than $45.

Our advice is this:
  • Buy your baby monitor only from a retailer with a liberal return policy
  • Carefully unpack the monitor so it can be returned without difficulty
  • Immediately test it in your home to make sure interference is not an issue and you have adequate range capability
  • Try it in all the areas you'll use the monitor most (typically your master bedroom, living room, and kitchen areas), and turn on all your wireless phone, wifi network, and other devices that might interfere
  • Keep in mind that interference may also come from a neighbors home (test it at night when other baby monitors in the neighborhood will be turned on)
  • If interference or range is an issue in your home, immediately return the monitor. It's not something you'll be able to fix, and it's not worth the loss of sleep you'll incur suffering through an interference issue.

Sound Activated Monitoring with Adjustable Sensitivity
We think you'll appreciate a baby monitor that offers a sound activation feature, and highly recommend it.

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The Sony BabyCall makes it very simple to turn on/off their sound activation feature (which they abbreviate as "Voice Act" or "VOX" in their documentation)
Credit: BabyGearLab Staff
The best baby monitors offer an ability to filter out background noise and are tuned to the sound frequencies of a baby crying. While baby is silently sleeping, the best monitors offer the ability to filter-out the background noise and hiss that might otherwise occur and become totally silent. Yet, when baby cries out, the monitor tunes-in immediately and even amplifies the sound so you wake up and can check on baby.

Different monitors describe this feature with different words but they all refer to the same thing: microphone sensitivity, background noise filter, sound sensitivity, sound-activated, or voice-activation (VOX). We just the term "Sound Activated" in our review.

While to a 1st time parent this feature may not seem important, it can play a key role in allowing you to sleep better. Why? Because most parents will want the monitor set to relatively loud volume to assure they hear it (and wake up) when baby cries. But, with the monitor volume turned up loud you'll invariably hear a background hiss that sounds like a radio tuned between stations combined with whatever subtle sounds exist in baby's room. This background noise can be very annoying and prevent you from getting much needed sleep. With the sound activated feature enabled, that same background hiss is reduced to absolute silence which really help you fall asleep. Yet, when baby cries, or a significant noise occurs in the room, the monitor kicks-in within seconds and you can hear everything going on in the room.

A critical feature from our point of view is the ability to easily turn sound activation off from the parent unit so you can briefly hear everything in baby's room, make sure the monitor is working properly, and get the monitor volume adjusted correctly. Then you turn the sensitivity filter on so you can get some sleep.

The very best monitors, like the Angelcare Deluxe or the Philips Avent DECT, give you adjustable control over the sound activation's sensitivity from the parent unit. This can be very helpful in practice to allow you to adjust so as to barely tune out background noises, yet assure that the slightest sound above the background level comes through on the monitor.

Many of the lowest cost baby monitors offer no sound activated feature. We recommend you avoid them. We've listed which monitors offer the feature in our comparison table. If you value your sleep, put this feature on your must-have list.

Battery Life - Does it Really Matter?
Battery life is not a major consideration. Almost all the monitors we reviewed offer rechargable parent-units with battery life over six hours. And while the lowest-cost baby monitors offered the best battery life, you won't see us recommending them because of it.

Battery life comes into play as you temporarily move the monitor away from it's normal location (typically the master bedroom). This comes up all the time if you only have a single parent-unit, as you'll want to have the monitor with you in the kitchen, office, and living room while baby sleeps. Relocating the power supply every time you move from one room to another is a hassle.

We recommend getting a two parent unit version of the baby monitor if there is one available, so you can keep each both parent-unit's plugged into a charger most of the time (one in the kitchen, one in the master bedroom), and reduce the number of times you need to rely on battery power.

In general, we found the video monitors offer poor battery life compared to sound or sound/movement monitors which means you'll be more often relocating the power supply along with the monitor.

Also, keep in mind that battery life degrades after use. By the time your baby is a year old, your baby monitor's battery life will be a fraction of what it was when new. We recommend that you replace the batteries with new rechargeable batteries if battery life degrades significantly.

Risk of Strangulation
A primary safety consideration with a baby monitor is making sure the cord(s) can't be reached by baby reaching through the crib. The power cord and any other cords (such as the movement sensor cord on Angelcare or the network cable on Y-cam) should be secured well out of reach of the baby. Angelcare offers a video on this topic.

While a newborn initially lacks the mobility to reach through a crib, we urge you to take this into consideration from the get-go, since you'll have forgotten about cord placement months later when baby is mobile and can reach the cords.

Video monitors present challenges to place the camera near the crib, yet assure that that both the camera and all cords are out of reach of baby. The best vantage point for a video camera is high enough to look down on the crib, and relatively close to the crib. To locate the camera properly, you may need to secure the camera on it's own shelf. In any event, make sure all cords are completely out of reach.
RJ Spurrier
About the Author
RJ Spurrier is a father of two, an avid outdoor enthusiast, a software developer and a tinkerer. He heads up Test and Measurement Operations for BabyGearLab and plays a key role in architecting the technical tests used to objectively measure performance of competing products. Spurrier is sometimes referred to as "my techie husband" by BabyGearLab's founder and Mom-in-Chief, Dr. Juliet Spurrier. RJ holds a patent in digital imaging technology and was formerly a Vice President at Adobe Systems. He earned his B.A. from the University of California at Berkeley in robotics and automated control systems.