The Best Crib Mattresses for a Safe, Sound Slumber

For years, there were two main crib mattress categories: innerspring and foam. However, over the last decade, innerspring mattresses have fallen in popularity and a third category has emerged: specialty mattresses, mostly breathable core. The best place to start your crib mattress research is to learn about the different types of crib mattresses.

An innerspring crib mattress is a traditional mattress that has steel coils inside, making it sturdy and resilient. Above the coils, innerspring mattresses have layers of different cushioning materials, such as polyester, cotton or foam. Innerspring mattresses are described by their coil count, which is the number of steel coils in the mattress. The more coils, the more supportive the mattress. You’ll also sometimes see steel gauge mentioned. This refers to the thickness of the coil; lower numbers mean thicker coils. Some innerspring mattresses also have metal border rods that provide stability around the edges.

Innerspring mattresses can be pricey, especially if you’re looking into a higher coil count. These mattresses also tend to weigh more than other types of crib mattresses.

Foam mattresses are typically made from polyurethane, a foam resin. They are lightweight and durable and are usually the least expensive mattress option. However, some parents have concerns over their materials and chemical emissions. 

Specialty crib mattresses include breathable “air core” mattresses that use a type of food-grade polymer to create a woven mattress core made mostly of air. Air core mattresses are lightweight and breathable, but tend to be more expensive than many other crib mattresses. Also know that if you’re researching a breathable crib mattress, there is no evidence that these types of mattresses are any safer than innerspring or foam options and have not been proven to reduce or protect against SIDS. However, there is no data to argue against them, either.

Other specialty mattresses may be made from various organic materials, such as cotton, wool, natural latex or coconut fiber.

Focus on these crib mattress features as you compare your options and narrow down your picks.

Size and fit

The CPSC regulates full-size crib mattresses. Per the full-size baby crib guidelines, all full-size crib mattress dimensions must measure at least 27 1/4 inches wide by 51 1/4 inches long and have a thickness not exceeding six inches. The mattress should fit snugly against the frame of your crib. You shouldn’t be able to fit more than two fingers between the mattress and the crib.

If you’re shopping for a mattress for a mini crib—a smaller version of a full-size crib—note that CPSC regulations require that all mini cribs are sold with a mattress included. However, these mattresses are often fairly thin and skimpy, so you may want to purchase an additional mattress separately. (Mini cribs fall under what the CPSC calls “non-full-size baby cribs,” which have their own set of specific compliance guidelines. There’s also no standard mini crib size; instead, they must fall within a certain set of measurements. Always be sure to measure both the interior of your mini crib and the mattress you’re hoping to use to be sure they fit.) 

Be sure the dimensions of the mini crib mattress you choose match the interior dimensions of your particular mini crib. For an extra safety check, be sure that there isn’t more than a half-inch gap between the perimeter of the mattress and the perimeter of your mini crib when the mattress is centered and isn’t being compressed. You’ll also want to check to be sure there isn’t a gap greater than one inch at any point when the mattress is placed against the crib’s perimeter.

Firmness

Crib mattresses are firmer than adult mattresses—for a reason. The American Academy of Pediatrics’ (AAP) safe sleep guidelines recommend that babies sleep on a firm, flat sleep surface. Crib mattresses are specifically designed to keep babies safe, help reduce the risk of SIDS and support their growing bones while they sleep.

Always keep firmness top of mind when shopping for a crib mattress and choose one that doesn’t sink with the weight of your baby. If you’re shopping for an innerspring crib mattress, look for one with a higher coil count. (If steel gauge is also listed, look for a lower number to ensure it’s more firm.) When choosing a foam or specialty crib mattress, test the mattress by pressing your hand firmly down on it and see how long it takes to regain its shape. The faster it springs back up, the better.

Many crib mattresses are double-sided. These mattresses have a firmer infant side and a softer side that is more appropriate for toddlers who still use a crib or convertible toddler bed. You’ll want to use the firmer infant side at least through your baby’s first birthday, then flip to the softer toddler side.

Materials

There are two things to keep in mind when considering the materials in your crib mattress: the cover and the filling.

Messes are inevitable, so the crib mattress you choose should be easy to clean. Consider a crib mattress with a waterproof outer cover built right in or one with a removable, washable cover. Also, pay attention to how “noisy” the mattress and cover may be. Some waterproof mattresses, especially lower-priced options, make crinkling sounds with every movement, which can disturb a sleeping baby.

Note that some crib mattresses are covered with vinyl. Some types of vinyl, like PVC (polyvinyl chloride), contain phthalates, a group of chemicals sometimes called plasticizers that are used to make plastics more flexible and durable. Some types of phthalates have been linked to negative effects on the reproductive system of animals, although more research is needed to fully assess the human health effects. If this is something that concerns you, avoid any crib mattresses that contain PVC.

When thinking through the type of filling you prefer in a crib mattress, there are several considerations. Innerspring crib mattresses use materials like cotton or foam around the inner coils. These types of crib mattresses tend to be heavy but well-made and durable. Foam mattresses are generally filled with high-density polyurethane foam, a light, durable and supportive foam that’s used as cushioning in many different consumer products like bedding and furniture. They tend to be less expensive than innerspring mattresses but may wear out sooner. Polyurethane also emits something called volatile organic compounds (more on that below), though in very small amounts—but if it’s something you want to avoid altogether, consider a different type of crib mattress.

VOCs

VOCs—volatile organic compounds—may be something you hear about when researching crib mattresses.

“There are chemicals used in the manufacturing of crib mattresses—as in the manufacture of all furniture, rugs, etc. And crib mattresses do emit volatile organic compounds which, in high doses, can irritate breathing,” explains Oster. 

“However: the volume of [VOCs] emitted from crib mattresses is fairly low, and similar to other exposures people are getting in the world. Moreover, there is not much reason based on the data to be worried about low levels of exposure. At high levels, absolutely. But crib mattress level exposure is not like, say, paint stripping,” she explains.

If you’re committed to lowering your exposure to VOCs, Oster recommends avoiding mattresses with polyurethane, as mentioned above. 

Certifications and Designations

All crib mattresses made in the US must pass the same federal safety standards, but if you’re interested in further certifications, here’s what to research.

• GREENGUARD Gold Certified. The GREENGUARD Gold Certification ensures that a product meets all industry standards for low chemical and VOC emissions.

• GOTS. GOTS, the Global Organic Textile Standard, is the worldwide processing standard for organic materials. It requires that at least 95% of a crib’s mattress materials are certified organic and prohibits the use of certain substances like polyurethane and chemical flame retardants.

• CertiPUR-US Certification. CertiPUR-US is a certification for foam that ensures it meets certain standards for content, emissions and durability. CertiPUR-US foam is low VOC and phthalate-free and is made without ozone depleters, mercury, lead and other heavy metals. It’s also free of formaldehyde and certain chemical flame retardants.

• GOLS. The Global Organic Latex Standard requires that a mattress made with latex is 95% organic latex. (There are also restrictions on the other five percent of the mattress’s components.)

Weight

You’re going to be changing a lot of sheets over the next few years. Unlike when changing an adult bed, you’ll be picking up your crib mattress to get the fitted sheet on and off every time. If you’re on the smaller side or simply don’t want to wrangle with a heavy mattress, consider weight when you’re selecting a crib mattress. A lighter mattress makes sheet changes both easier and faster.

Price

Crib mattresses come in a huge range of prices, from under $100 to upwards of $500 or more. While more expensive mattresses tend to be made from higher-quality materials, there’s no need to splurge for a high-end crib mattress if it’s not in your budget. Many mid- to lower-priced mattresses are safe, comfortable and durable, and most run between about $100 to $300. Spending less than that is possible, but many parents report that very inexpensive mattresses often sag quickly, rip or don’t protect from leaks or spills, and therefore aren’t recommended.

According to the AAP, the most common falls occur when a baby tries to climb out of their crib. To make baby’s room safe, lower the height of your crib mattress as your baby gets older and more mobile." While your baby is an infant, you’ll want to use your crib on its highest mattress height setting so it’s easy to get your little one in and out. As soon as they can sit, lower the mattress to a level where they cannot fall out either by leaning against the side of the crib or pulling themselves over. Adjust the mattress to its lowest position before your child learns to stand.