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How Big Is A Crib Mattress In Size? [FIND OUT HERE]

How Big Is A Crib Mattress In Size? [FIND OUT HERE]

Among the first things new parents do when preparing to welcome a newborn baby is to create a warm and safe sleep environment. That means you will need a comfortable and sizable crib and crib mattress. But are you aware of the crib mattress dimensions to consider?

The standard size of a crib mattress is 27 ¼ inches in width by 51 ¼ inches in length. Standard-sized crib mattresses have a maximum thickness of 6 inches. Crib mattresses also come in mini versions and unique shapes. You get to choose the correct dimension depending on your room size, style, and crib.

Dimensions for crib mattresses are typically standardized under federal government regulations because child safety is quite critical. Besides their length and width, their thickness is also standardized. This article covers all the basics of crib mattress dimensions.

Baby coming happy

What Are Crib Mattresses?

A crib mattress is a mattress for babies. It is smaller and firmer than adult mattresses. Their firmness helps keep babies safe and supports their growing bones as they sleep. Firm mattresses also help reduce the risk of crib death, medically known as sudden infant death syndrome (SIDS).

What Size is a Crib Mattress?

The standard size for a crib mattress is 27 ¼ inches in width by 51 ¼ inches in length. The mattresses feature a maximum thickness of six inches. This is the preferred choice for most parents because of its advantages. For instance, most manufacturers design them so that you can easily convert them into toddler mattresses as the child grows. More so, standard-sized mattresses are more expensive than their counterparts.

While crib sizes get standardized under federal government requirements, the market still offers an array of mattress sizes depending on the crib type. Below are some crib types and their sizes;

Mini cribs. These cribs typically measure 24 inches by 38 inches. Mini cribs are fantastic for smaller nurseries and parents who want their kids to share a room. Their small size also makes them cheaper to buy and easy to install. Some mini cribs come with wheels for more accessibility.

Shaped cribs. There is no standard size for shaped cribs. The dimensions typically differ depending on the crib shape. Note that they are generally bigger than mini cribs but smaller than standard-sized ones. Shaped cribs are a fantastic choice for parents that want something custom and adorable.

How to Buy a Crib Mattress?

Choosing a crib mattress can be a hectic yet satisfactory task. The search process needs much consideration since it impacts your child's health and comfort. As we already know, among the most vital elements to consider is the size. However, there are several other factors to weigh. Below is a buying guide for a crib mattress.

Consider the Crib Size

The ideal mattress should go well with the crib size. Going for a mattress that fits snugly in the crib with as little space as possible is a wise move. That guarantees your baby's safety since a big gap can become hazardous. Such a bed is also easy to play around with.

Do Not Forget about the Firmness

A good crib mattress should be firm and solid. These features protect your baby from SIDS. SIDS is the third top reason for infant deaths in the United States; statistics reveal that the U.S. experiences around 2500 annual infant deaths due to SIDS. Again, soft mattresses can increase the chances of suffocation. When buying a crib mattress, test the firmness by pressing around the edges and center.

Ensure the Mattress is Breathable

Breathability matters a lot when choosing a crib mattress for your baby. This feature is vital to your baby's healthy sleep cycle. Heat causes your baby to keep waking up in between their sleep cycle. A breathable mattress helps promote sufficient airflow in the bed and prevents overheating. Latex crib mattresses are an excellent choice because they are naturally cool.

Prioritize the Thickness

Mattress thickness is vital for your baby's well-being. The recommended thickness for crib mattresses is six inches. However, the thicknesses differ depending on the manufacturer. Go for a mattress with a thickness of between five to six inches. The mattress type will also influence the ideal thickness. For instance, innerspring crib mattresses are usually five to six inches thick, while foam mattresses are four to six inches thick.

Consider the Cost and Durability

In addition to all the above elements, we cannot assume the cost and durability of a mattress. The crib mattress' materials, dimensions, and design usually influence its durability. Added features like waterproofing will alter the cost. The most durable mattresses tend to cost more; a crib mattress is an investment, especially if you want it to last longer. The mattress size impacts its cost. For instance, standard-sized mattresses are more expensive than mini versions.

Take Note: With all the considerations for choosing a mattress, we recommend starting your search early. It's because you will not make a rushed decision when shopping at the last minute.

Advantages of a Crib Mattress

Purchasing an excellent crib mattress will benefit you and your baby. Here is a list of some of these benefits.

  • It ensures the safety of your child as they sleep.
  • It helps you teach your child to sleep independently without worrying about them.
  • A crib mattress is a perfect addition to your baby's nursery.
  • The mattress allows your baby to sleep comfortably.

How Big is a Crib Mattress in Size? FAQs

Whether you are a new parent or not, choosing the perfect crib mattress size can be draining. Most people have a lot of questions. Below are some of these questions and their answers.

What are the average crib dimensions?

The average crib dimensions differ depending on the crib type. Here are the average crib dimensions based on the type;

  • Standard cribs – these baby beds measure 28 by 52 inches.
  • Mini cribs – these baby cribs measure 24 by 38 inches.
  • Shaped cribs – the average size for shaped cribs differs depending on the shape.

What size is a standard crib mattress?

A standard crib mattress size is 27 ¼ by 52 ¼ inches. You never have to worry about the standard size changing because the government regulates it.

What size are mini crib mattresses?

Unlike standard full-size crib mattresses, the government does not regulate mini crib mattresses. Therefore, their sizes may differ depending on the manufacturer and design. Most of them usually come in dimensions of 24 by 38 inches.

crib mattress wood style

Are the crib mattresses all the same size?

No, not all crib mattresses are the same size. Many assume they all have the same size because of the federally regulated dimensions. However, there are smaller ones called mini crib mattresses. In addition, some crib mattresses are also uniquely shaped. Shaped crib mattresses feature varying measurements based on their shape. Simply put, the mattress sizes differ depending on the crib.


Planning a nursery is a big deal for most parents. A significant part of designing a baby nursery is choosing the crib. With buying the crib, comes selecting the crib mattress. One of the vital considerations for choosing a crib mattress is the size. There are three types of crib mattresses; standard, mini, and shaped.

Standard crib mattress sizes are government regulated and measure 27 ¼ by 52 ¼ inches. On the other hand, mini mattresses measure 28 by 38 inches, while shaped cribs have no specific size. Now that you have all these details about crib mattress dimensions, feel free to shop for what suits you best today.

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