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Can’t find the right size mattress for your child? We know the struggle and we’re here to help. In this article, we tell you about the most common kids mattress sizes and how to choose the right mattress for your kids.
Most common kids mattress size
| Mattress Size | Dimensions |
|---|---|
| Standard crib | 28" x 52" |
| Mini crib | 24" x 38" |
| Shaped crib | No fixed dimensions |
| Twin | 38" 75" |
| Twin XL | 38" x 80" |
| Full | 54" x 75" |
| Queen | 60" x 80" |
| King | 76" x 80 |
Mattresses for kids range from small crib mattress sizes all the way up to standard adult bed sizes.
Since getting a good night’s sleep is essential for your child’s growth and development, it’s best for them to sleep on a mattress that makes them feel comfortable and well-supported.
You can’t just let your infant sleep alone on a twin mattress. That would be absurd. It’s also inappropriate for your 6-year old to keep sleeping on a crib mattress.
Choose the mattress size that’s best suited to your child’s age, body type, and needs. Does it give them enough space? Does it fit their bedroom nicely? Is it safe? Ask yourself these questions before deciding.
If by some chance you aren’t that familiar with the different kids mattress sizes, we’ve listed them for you below starting with the types of crib mattresses.
Crib mattress sizes
- Standard-size crib mattress
- Mini crib mattress
- Shaped crib mattress
Specifically designed for infants and toddlers, crib mattresses are much smaller than standard mattresses.
Crib and toddler mattresses are made with materials such as foam or latex, but not with innerspring coils. In addition, crib mattresses have to meet strict safety standards to be suitable for babies.
Standard-size crib mattress
A standard-size crib mattress’s dimensions are 28″ x 52″.
It’s the most common crib mattress version and it has a rectangular shape like the standard mattress sizes. A standard-size crib mattress is your best option if you have an infant or a small toddler.
Quick reminder: Make sure that the crib mattress snugly fits the crib frame. There must be only half an inch of space between the mattress and the crib sides to prevent your child from trapping their head and suffocating.
Mini crib mattress
At 24 inches wide and 38 inches long, mini crib mattresses are best suited for children who are 1-year-old and below.
And as I mentioned portability, these mattresses can be easily folded for travel and storage.
Shaped crib mattress
Unlike standard and mini crib mattresses, a shaped crib mattress does not have fixed dimensions.
It can be shaped like a rectangle, or it can also have a round, hexagonal, or oval shape. Due to their unique shapes and designs, they are usually sold as a set which includes both the crib and the mattress.
You can use a shaped crib mattress as an extra sleeping space for your child. But we don’t recommend it if you’re searching for a long term option. Standard-size crib mattresses still offer the most value and benefits.
Twin mattress
Moving on to standard mattress sizes, a twin mattress’s dimensions are 38″ x 75″.
It’s the smallest size available and it we recommend it for children and some teenagers. A twin mattress is perfect if your child is transitioning from a crib to a bed. 5 Little Monkeys and Maxtrix are examples of brands that make twin-sized mattresses for kids.
Moreover, twin mattresses are a good fit for smaller bedrooms and are cheaper than the larger mattress sizes. The one obvious drawback of a twin mattress is that it’s not suitable for taller individuals.
Twin XL mattress
As the twin’s longer counterpart, a twin XL mattress dimensions are 38″ x 80″.
Twin XL mattresses offer all the benefits of a twin bed but with added length for taller sleepers. If your kids are growing teens, we recommend twin XL mattresses so they can sleep comfortably and enjoy extra legroom.
College dorm rooms also tend to have twin XL beds which require this common dorm mattress size. Keep this in mind if you have kids that are going to college.
Full-size mattress
Also known as a double bed, a full-size mattress measures 54″ x 75″.
Now this is a bigger mattress, but still nowhere near as large as a king-size mattress. Full-size mattresses are best for single adults, but they can also be used for kids. If you have two kids that share a bed, a full mattress is a solid option that offers ample sleeping space.
However, if you’re a taller individual like me, you might want to opt for a longer mattress like the Full XL.
Queen mattress
Queen is the most popular mattress size and its dimensions are 60″ x 80″.
Although it’s mostly used by couples, you can also use a Queen-size bed for your kids. Depending on their body sizes, up to three smaller children can fit on a Queen mattress.
If you have a child who’s overweight, a Queen mattress can offer adequate space for them to get good sleep.
King mattress
Last but not least, a King mattress measures 76″ x 80″.
It’s the largest standard mattress size and it’s commonly used by couples in master bedrooms. King mattresses are quite expensive, so you rarely see them being used for children. However, parents can co-sleep with one toddler on a King-size bed.
On the other hand, if you’re looking for a mattress where you can co-sleep with several children, we suggest getting an oversized mattress. Alaskan King and Wyoming King mattresses are excellent options.
Finally, if a King-size mattress gives you the width that you need but it lacks length, we recommend getting a California King mattress for some added legroom.
What is a good toddler mattress size?
Twin mattresses are the perfect mattress size for toddlers who are transitioning from their crib.
Twin beds are really affordable and will likely last until their teens. Excellent for small spaces, a twin mattress is a worthwhile investment for your child’s bedroom.
Another good, albeit less common toddler mattress size is the small single bed. It measures 30″ x 75″ and it’s best suited for children below the age of 10. Small single mattresses can also fit in narrower bedrooms.
How to save space if you have multiple kids
What to do if you have a lot of kids and very little space? Check out the following space-saving options which allow your children to sleep comfortably at night even in a tiny bedroom.
Bunk beds
With bunk beds, you get two beds for the floor space of one. A bunk bed is a single unit that features two beds with a lower and upper berth. Bunk beds commonly use twin mattresses and they are great for children who are sharing a bedroom. Make sure your kids are the right age for bunk beds before you go out and buy one.
Most bunk beds also have drawers on the lower bunk which gives you space to store your child’s stuff. It’s just the perfect option for saving space and letting two kids sleep in one small bedroom.
Learn more in our bunk bed dimensions article.
Pop-up trundle beds
A pop-up trundle bed is another great option that saves space during the day and gives your kids a comfy bed at night. Made with a two-in-one design, you have a traditional bed frame on top and a mattress platform with wheels below it. Just pull the lower bed out at night and push it back under the top bed during the day to save space.
Daybeds
Daybeds are usually three-sided bed frames that can be used as beds at night and sofas during the day. Available in a wide variety of sizes and upholstery designs, daybeds are great for bedrooms, living rooms, and even home offices. You can use a daybed to save space in your kids’ bedroom.
Cabin beds
A cabin bed is an elevated sleeping platform that features a lot of space below for your child’s things. It’s a great option if you want to maximize the floor space of your child’s bedroom.
How to choose the right size mattress for your kids
Now that you know all about the different kid-sized mattresses, it’s time to select the right size for your kids. Just keep these three factors in mind and you’ll be good to go.
Age
First, consider your child’s current age. Crib mattresses are best for infants, and twin mattresses are great toddler beds. If you have older kids, you can also consider a twin XL or a full-size mattress for a wider sleeping space.
Space
What’s the available space in your child’s bedroom? If it’s a bit cramped, then you should opt for a smaller mattress like a twin or maybe a bunk bed. But if there’s enough space, you can think about buying a full mattress especially if you’re child is a growing teen.
Are they sharing a bed with siblings or parents?
If you have several kids or you practice co-sleeping, you’ll be needing a bigger mattress. King-size mattresses can be great for accommodating one child with parents. If you have two or more kids, we suggest getting a Family bed for the best sleeping experience.
FAQs
A standard-size crib mattress will be best for children who are 1-3 years old.
An 8-inch mattress is good for kids who have transitioned from a crib to a bed. However, we do not recommend 8-inch mattresses for infants who are sleeping in a crib. The maximum mattress height for crib beds is 6 inches for safety reasons.
Yes, a 4-year-old will fit comfortably in a toddler bed.
Yes, most 12-year-old kids will fit in a twin bed. But if they grow taller, they would be better off sleeping on a twin XL mattress.
A twin mattress is a great option for a 7-year-old. It provides enough space and it will last a couple of years until the child outgrows it.
Yes, most crib and toddler mattresses have the same dimensions.
A toddler bed or a small single bed is best for a 4-year-old.
A classic medium-firm mattress should be good for a 10-year-old kid. Not too soft and not too firm, a medium-firm mattress is just right for most individuals.
Conclusion
Choosing the right-sized mattress for your kids is not that difficult if you know about the different mattress sizes. With options ranging from crib beds to king mattresses to space-saving options such as bunk beds, you should decide on what fits your child’s needs the best. Remember, consider your child’s age, their bedroom space, and if they sleep with a sibling.
Next step: Read our Saatva Youth mattress review. The Saatva Youth is designed specifically for the needs of growing kids. We tested it out and discovered a few different pros and cons so you can decide for yourself if it’s right for your children.
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