How to Prepare Your Crib Mattress Size, First Time Mom

Infants can spend approximately 18 hours daily sleeping. A crib bed mattress is among the most important purchases when getting ready for your new arrival. So what to look for in a crib bed mattress? We’ve broken down the basics in our crib mattress size.

Start From Standard Size Mattress

There are many baby cribs designs on the marketplace – modern, conventional, convertible, designer, bare-bones, take your pick! No matter the design, any crib produced and offered in The United States and Canada should be built to fit a complete size baby crib mattress.

So, what are the measurements of a baby crib mattress, and for how long is a crib bed mattress? All North American baby crib mattresses must measure between 51 3/4 to 53 inches in length and 27 3/8 to 28 inches in width. This is equal to around 130 cm and 70 cm. Thickness can vary from 4 to 6 inches (15 cm), but no more than that because of the regulation.

A standard-size crib mattress can last up to three years with the baby.

Mini crib

Mini baby cribs might be the best option for your lifestyle if space is an issue. Nevertheless, it is essential to bear in mind that mini cribs do not follow strict regulations like standard cribs. These cribs come in all sorts of sizes and shapes.

newton baby

While some mini baby cribs can be similar to a standard crib, they are substantially smaller sized. Many rectangle-shaped mini baby cribs have an interior measurement of 24 inches (10 cm ) in width and 38 inches (96 cm) in length.

When acquiring the mini baby crib, take notice of the dimensions offered by the manufacturer and choose your bed mattress size appropriately. Mini cribs will come with the mattress. This is also needed to note in case you’ll need replacement.

Crib Mattress Size & Dimensions

Size is one of the three primary elements you wish to consider when mattress shopping, the other 2 considerations are bed mattress type and firmness. With many choices and sub-categories to choose from, it can feel frustrating to identify the best bed mattress for you.

Consider your bedroom’s size and your budget, in addition to how you’ll utilize the bed mattress. A mattress you’ll show your partner requires a different size than a bed mattress for a small visitor bedroom.

Check out the chart below to determine the mattress size sold in the market:

crib mattress size

So remember, we’re looking for a “Crib” size, and for “mini crib” is non-standardized and will always come with the crib. If you want to convert a crib to a full-size bed, you can also look in the chart.

  • Your crib must measure between 27 3/8 to 28 5/8 inches wide and between 51 3/4 and 53 inches long.
  • Bed mattresses are designed to be somewhat smaller sized than these basic measurements. To be sure, utilize your tape measure to check that there is not more than a 1 1/4″ gap between the mattress and crib (the two-finger gap rule).

Portable Crib Mattress Size

If you travel a lot, this is a must-have, and measurement is inevitable. Pick something like Graco Travel Lite. They have 33.5 inches long and 32.25 inches wide, a 25% smaller than traditional playards to safe space. So they fall on the non-standard crib mattress size.

Also, you can choose Graco Pack and Play On the Go Playard, which has dimensions of 40 x 28.5 x 29 inches, is still portable and is less than half the price of the Graco Travel Lite.

For your child’s safety, we do not advise utilizing any after-market mattress or additional soft buntings in our playards. Unlike baby cribs with stiff sides, the playard has flexible sides, and playard bed mattresses are specially developed to prevent suffocation. Using a thicker or a various sized mattress/pad may enable a child’s head to get between the mattress/pad and the side of the playard, causing suffocation.

crib mattress size

When your baby is eight months or more, it’s time to remove the bassinet because they can crawl and lifting themselves by holding onto the bars.

crib mattress size
Careful Shopper

Crib Mattress Size IKEA

IKEA Nordic cribs are a popular option among parents today. They are most favorable if you check out the evaluations. Their total credibility is excellent. They adapt to your youngster’s development, and purchasers appreciate that there’s an Ikea baby crib for each budget plan.

When purchasing the baby crib mattress, the brand name decision modifications. Lots of moms and dads purchase non-Ikea bed mattresses to match the IKEA crib they have currently picked.

IKEA Gonatt

Now, the different designs of IKEA cots have little different sizes. The Stuva and Sundvik are a little bit larger than the Gonatt or the Gulliver. On the other hand, all bed mattresses that feature these cribs are always 27 1/2″× 52″. You can see that they satisfy American standards but are close to the tiniest.

We suggest you test the mattress size with the two-finger gap test. It cannot be smaller than your two-finger gap and no bigger than the IKEA standard crib mattress. Many brands come with 27 1/4 inch x 51 5/8 inch or even close to the IKEA’s size. You can choose based on your preference, like an organic, memory foam, or softer mattress.

Graco Solano Crib Mattress Size

Graco Solano 4-in-1 Convertible Crib comes with the dimension of 29.61 x 55.91 x 41.42 inches. The thickness of the crib is between 0.5 to 0.8 inches. For mattresses to fit their size and still pass the two-finger gap, rules must have no more than 27 1/2″ and 52″ in size.

Graco Premium, which measures 27.6″ x 52″ fit this crib very well. It’s snuggle and passed the two-finger gap test. You can pick any American Standard mattress size. Only keep in mind this crib is slightly bigger, so you’ll need to pick from the high, wide range.

Crib Mattress Size Bunk Beds

We don’t recommend bunk beds for toddlers under ten years old because of safety reasons. It is also safe to assume it will come in a standard size, start from crib size (21.5″ x 51″). For other sizes please refer to our chart above.


Other Crib Mattress Size

Europeans have a standardized smaller mattress size which is 23″ x 47″. So if you’re moving from Europe (the UK has a different size as well, which is 27.5″ x 55″) and need to bring your crib, it will be more difficult to find it in the US. Also, many European products do not meet the flame retardant standard that is now a requirement for the California regulation (117 ). If you can’t find a website that will ship a European-size crib bed mattress to you, possibly you can have it shipped to a good friend who still lives there.


With many different types of cribs come many different sizes of mattresses. Things to remember here: you must first pick your mattress type, whether it’s organic, soft material, or memory foam, then the gap size can’t be any wider than two fingers wide to your crib’s edge. Another thing is for your baby’s safety. Before eight months old, you need to remove the bassinet because of the risk of baby fall.

We hope this post is useful for you to pick the right mattress size.


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