Mini Crib Dimensions and Guidelines (with Drawings)

A mini crib is a smaller version of a standard crib. They are suitable for use from birth right through to age 2 (or until the baby reaches 45 pounds in weight), so they can be used instead of a regular-sized crib, or they can be used as a temporary sleeping space for the baby.

Some parents love mini cribs, while others find they aren’t a necessary purchase. Here, we will look at the dimensions of mini cribs compared with other baby sleeping solutions to help you identify which will work best for your space and your family.

Here is a quick answer illustrated with a diagram below.

The average mini crib mattress is 24 inches wide and 38 inches long. In comparison, the standard crib mattress has an average size of 28 inches wide and 52 inches long.

Mini Crib Dimensions

Crib Vs. Mini Crib

Crib Vs. Mini Crib

Standard cribs are regulated by the government to be a certain size, usually at 28 inches wide and 52 inches long. This means that all standard cribs, all standard crib mattresses, and all standard crib sheets will be the same size. This is useful as a parent because it means you can buy your crib accessories from any store and be sure they will fit your crib; however, the reason that crib sizes are standardized is for safety.

If cribs and crib mattresses come in different sizes, then it is likely people may end up using a mattress that doesn’t perfectly fit their crib. This can result in a baby slipping down the gap around the edge of a mattress and suffocating.

To ensure safety and reduce the risk of SIDS, all crib mattresses and cribs are the same size, so that you can use a mattress from one manufacturer and a crib from another manufacturer, safe in the knowledge that they will fit perfectly and produce a secure spot for your baby to sleep.

Having sheets that perfectly fit the crib mattress also ensures that there is no loose or baggy material, which again could lead to suffocation. Compared to standard cribs, mini cribs are not size-regulated. This means that the exact size varies between manufacturers.

Typically most mini cribs measure roughly 24 inches wide and 38 inches long, but this is not exact. This means that if you buy a mini crib, you will need to buy the mini crib mattress designed to be used with it and mini crib mattress sheets, which are sized accordingly.

This isn’t too inconvenient for most people, but it is something to be aware of so that you don’t buy two different sizes of mini crib and mini crib mattress, which could inadvertently put your baby in harm’s way.

Benefits of a Mini Crib


A mini crib is not as portable as a pack n play, but it is vastly more portable than a full-sized crib. While a standard crib is intended to be constructed in the nursery and remains in the same place, a mini crib can be set up in the parents’ room while it is a newborn and then easily moved into the nursery when the baby is old enough to sleep alone.

This could be really handy because guidelines suggest that a baby should spend the first 6 months of life sleeping in the same room as its mother, which might be problematic if you were going to use a full-size crib. Most mini cribs can be folded down, which makes them a good sleeping solution if you want to take your baby for a sleepover at another house, as you can take the mini crib with you without too much difficulty.


A mini crib is quite a bit smaller than a standard crib, with a typical length of 38 inches compared to a standard crib’s length of 52 inches. This is really useful if you have a small bedroom but want your baby to be able to sleep alongside your bed.

While many parents will struggle to fit a full-sized crib in their master bedroom, most will find a mini crib a much more suitable size. Mini cribs are also a great choice if you have a small nursery and you don’t want it to be dominated by a large crib, or if your baby needs to share a bedroom with another sibling and space is limited.


Mini cribs are less expensive to buy than standard cribs, and their mattresses are also less costly. If you are on a tight budget, then a mini crib could be a good way to save money and help you to live within your means. Many people get carried away with buying stuff when a baby is due to arrive, as we are told that there are so many ‘essentials’ a baby will need.

However, if you are trying to limit spending, then you’ll probably have realized that all a new baby needs are a safe place to sleep, a few outfits and blankets, and plenty of love. If you can’t stretch to pay for a full-sized crib, then a mini crib is a perfectly good alternative.

Disadvantages of a Mini Crib

Quickly outgrown

One drawback of a mini crib is that babies can outgrow them quickly. While babies can remain in a crib until 3 years of age, a mini crib is usually outgrown by age 2. This means if your 2-year-old isn’t ready for a toddler bed, then you’ll have to buy a standard crib anyway.

Fewer mattress and bedding options

The non-standard size of a mini crib makes it more difficult to find accessories, including mattresses and sheets. As babies tend to have spills, leaks, and accidents frequently, you will need a good supply of bed sheets that fit.

  • 28 inches wide inches by 52 3/8 inches long (interior dimensions)
  • The top of the crib rail, measured from the mattress, must be 20 inches high
  • The bottom of the crib mattress support must be 6 inches or so off the ground

The average crib mattress is 28 inches wide and 52 inches long, while the average mini crib mattress is 24 inches wide and 38 inches long

A mini crib is large enough for babies under two years of age and less than 45 pounds