How to Pick a Crib Mattress

Baby sleeping in crib

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Shopping for the perfect crib is one of the most fun parts of having a baby. You've done your research and found the perfect one to complete your nursery. Now there's only one thing left to do to set up an ideal sleeping environment for your baby: pick the right crib mattress.

Choosing a crib mattress is just as important, if not more, as choosing the crib itself. "Your baby is going to spend a lot of time on their crib mattress—newborns can sleep over 20 hours a day," says Elizabeth King, CEO and founder of Sleep Baby Consulting and a mom of three. "You want this to be a place that supports sound sleep and is safe for them."

Here, we'll discuss the different types of crib mattresses that are available, and share tips from top sleep experts on how to choose the best one for your baby.

What Kinds of Crib Mattresses Are Available?

Standard crib mattresses are all about 52 inches long by 28 inches wide, so what really differentiates them is how they are constructed and what materials they are made of. Here is what's available in crib mattresses being sold today.

Infant vs. Toddler Mattresses

Infant and toddler mattresses are the same size since many are designed to transition from crib to toddler bed when a child does.

One key difference between mattresses that are designed just for infants and ones that are designed to be used for both cribs and toddler beds is firmness. Crib mattresses must be firm to help protect a baby under age 1 from the risk of sudden infant death syndrome (SIDS).

Toddlers may prefer a softer surface to sleep on, and some manufacturers provide a two-sided mattress option: firm on one side for an infant, and softer on the other for an older child. You can simply flip the mattress over when your baby makes the transition to their "big kid" bed.

You may wonder when to switch a child from a crib to a toddler bed. Experts recommend keeping your child in their crib until they are about 3 years old unless they are regularly climbing out of it, causing a safety hazard. The American Academy of Pediatrics (AAP) recommends making the switch by the time a child is 35 inches tall (or when the height of the side rail is less than three-quarters of their height) to discourage falls from climbing out of the crib.

Memory Foam vs. Innerspring Crib Mattresses

Crib mattresses are usually constructed from memory foam or innerspring coils. One main difference between these two options is weight. Foam is typically the lighter option at around 5 to 13 pounds, whereas innerspring mattresses range from 15 to 30 pounds.

Organic and Non-Toxic Crib Mattresses

Organic mattress options, which are made from natural and non-toxic materials, are also available. Certified organic mattresses are often made with wool, cotton, or natural latex foam and will have a label showing a clearance by the Global Organic Textile Standard (GOTS). They tend to be pricier than foam and innerspring crib mattresses, but it may give you peace of mind to know that your baby is being exposed to fewer chemicals while sleeping.

How to Choose a Crib Mattress?

Safety should be your number one priority when choosing a crib mattress. It is critical to ensure it meets the safety standards of the U.S. Consumer Product Safety Commission (CPSC), which recommends a firm mattress that fits snugly in your crib.

In 2022, the CPSC approved new federal safety standards for all crib mattresses sold in the U.S. These new standards will address potential hazards like lacerations, suffocation, and entrapment.

Firmness

If you're concerned about your baby's mattress being too firm, you're not alone! "Some parents are concerned about the comfort of a crib mattress," says Cara Dumaplin, a certified pediatric sleep consultant for Taking Cara Babies and neonatal nurse. "They worry that mattresses seem too firm for a baby to sleep well. I understand this concern, but what we know is that a firm, flat surface is necessary for sleep safety."

The AAP clarifies that "firm" refers to a hard surface and does not indent when the baby is lying on it. "Great sleep is less about the comfort of a crib mattress and more about laying a healthy sleep foundation," adds Dumaplin.

Fit

According to the CPSC, the standard size of a proper fitting crib mattress is at least 27.25 inches by 51 .25 inches, with a thickness not exceeding 6 inches. This helps to protect a baby from becoming entrapped between the mattress and the crib and potentially suffocating.

"There should be a gap of less than two fingers between the mattress and the side of the crib," says Dumaplin. She explains that if you are using a bassinet, play yard, or portable crib, it's important to use the mattress that comes with the product.

It is understandably tempting to give your little one a blanket, pillow, or lovey to snuggle with in their crib, but these items should be avoided in babies younger than 1 year old. Resist the urge to add bumper pads, pillows, quilts, comforters, sheepskins, stuffed animals, or any other soft products into a crib along with the mattress, since they can potentially cause suffocation.

Added Safety Features

As mentioned, safety is paramount when it comes to baby mattresses. Many mattresses come with added safety features, and trying to decide if they are necessary can be overwhelming.

One of the biggest features advertised is a mattress' ability to reduce the risk of sudden infant death syndrome (SIDS), usually labeled as "breathable." The AAP states that there is no evidence to back these claims, but parents can use them as long as they meet CPSC safety standards. The best way to reduce the risk of SIDS in babies under 1 year is to avoid bed-sharing, place them on their backs on a firm surface to sleep, and keep soft items and loose bedding out of the crib.

Other mattresses advertise a flame-resistant material, which sounds appealing, but not exactly necessary. The CPSC safety standards already require all crib mattresses to meet flammability testing requirements before they are sold. Investigations have shown that extra chemicals claiming to improve this may pose a risk to your baby's health.

If you are concerned about chemicals, consider looking for a crib mattress that is Greenguard Gold Certified. "[This] means [the mattress] has gone through the most rigorous testing and adheres to the highest standard for a healthy indoor environment for children," says King. Most importantly, it means the mattress has shown to have little to no toxic chemical emissions.

When asked if she recommended a particular type of crib mattress, Dumaplin replied, "I’ve seen mattresses with really nice features: waterproof, washable, hypoallergenic, organic. There’s not a right or a wrong answer if the crib mattress is safely fitted and used properly. Any of these choices truly should be based on a family’s budget and lifestyle preferences."

How Long Does a Crib Mattress Last?

On average, crib mattresses will last around three to five years. But that can vary based on an array of factors, including how much wear and tear it receives and what material it's made of.

Some experts say a lower density foam mattress may not last as long as an innerspring mattress since it can lose its shape. Innerspring mattresses tend to last longer, depending on the number of coils and how hard the metal is.

Ultimately, it comes down to the quality of the mattress material. The better the mattress is made, the longer it will last against all of the common baby messes. Diaper blowouts, drool, vomit, leaky baby bottles, and more will take a toll on your baby's mattress, which may lead to the need for a replacement before your child graduates from a crib or toddler bed.

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9 Sources
Verywell Family uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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