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Did you know that bunk beds come in all sorts of sizes and not just the usual twin mattress? Known for being ideal for kids and teenagers, bunk beds are also great space-saving options for entire families. With sizes ranging from twin all the way to King mattresses, you can choose which size best suits you and your family. In this article, you’ll learn all about the standard bunk bed dimensions and how to choose a mattress for a bunk bed.
Standard bunk bed dimensions and sizes
| Bunk Bed Type | Dimensions |
|---|---|
| Twin | 38" x 75" |
| Twin XL | 38" x 80" |
| Full | 54" x 75" |
| Full XL | 54" x 80" |
| Queen | 60" x 80" |
| King | 76" x 80" |
Bunk beds are available in all standard mattress sizes except California King.
Your children can sleep in a bunk bed, as long as they’re within the bunk bed age limit. You can also use it for your dorm room if you’re in college. Bunk beds are a great option for anyone who wants to maximize their limited bedroom space and fit as many people as possible without sacrificing comfort.
It’s absolutely imperative that you get the correct mattress size for your bunk bed. It’ll help you avoid any accidents caused by mattresses popping and slipping over the safety rails. To ensure that you receive much-needed comfort as well as safety, let’s go into detail on each bunk bed mattress size below to help you choose the best one to suit your needs.
Twin
Twin beds are 38 wide and 75 inches long.
Also known as standard bunk beds, twin bunk beds are great for children and teens with average body types. In some cases, a twin bunk bed can also accommodate shorter adults who don’t have enough room for a bigger bed.
Twin XL
A twin XL bunk bed is 38 inches wide and 80 inches long.
Although most bunk beds are made for twin mattresses, twin XL bunk beds are designed for taller sleepers who need extra legroom. You can also use twin XL bunk beds for your guest room or your college dorm room.
Full
A full bunk bed is 54 inches wide and 75 inches long.
It’s best suited for single sleepers who want extra space to spread out. Although it is possible for two people to fit in a full bunk bed, it’s not going to be too comfortable unless it’s two kids or a couple who loves to cuddle. Some full bunk beds though also come with a trundle bed.
Full XL
For those looking for a longer option, a full XL bed is also 54 inches wide but 80 inches long.
Again, we recommend this bunk bed size for single sleepers but it can also accommodate taller individuals. A Full XL mattress is also the biggest possible mattress size for the top bunk of bunk bed mattresses.
Queen
A queen bunk bed is 60 inches wide and 80 inches long.
Queen bunk beds are extremely rare and are usually designed to fit a queen mattress on the bottom bunk and a twin XL mattress on the top bunk. Queen mattresses are popular for couples but you don’t usually see them on bunk beds.
A queen bunk bed can fit a couple on the bottom bunk and a kid on top.
King
King bunk beds are 76 inches wide and 80 inches tall.
King bunk beds are not viable for most people as you’re going to need a larger room for it. Like a queen bunk bed, King bunk beds will have a King mattress on the bottom bunk and a twin or twin XL mattress on top.
King bunk beds can usually accommodate a couple with one kid on the bottom and another kid on the top bunk.
Bunk bed heights
The different bunk bed heights are:
- Low loft
- Mid loft
- High loft
- Ultra loft
- Low bunk
- Medium bunk
- High bunk
- Triple bunk
- Corner loft
- Corner bunk
A standard bunk bed is usually 39 inches wide, 75 inches long, and 65 inches tall.
Bunk bed dimensions can vary depending on the design and style of the bed. You can learn more about the different bunk bed heights below.
Low loft
A low loft bed is 50.75 inches tall and has an under bed clearance of 33.5 inches.
This is a great option if you have a kid and their room has very little floor space. Although most loft beds offer under bed storage space, some low loft beds may not offer enough so that’s definitely something to watch out for.
Mid loft
A mid loft bed is 61.5 inches tall and has an under bed clearance of 44.25 inches.
It has the same benefits as a low loft bed but it should only be used for kids who are 8 years old and above. If your kid is younger than that, they might be more prone to accidents.
High loft
A high loft bed is 71 inches tall and has an under bed height of 52.5 inches.
With this bed, you will have much more under clearance to fit your child’s things or even small furniture such as drawers. We recommend this bed height for children who are 12 years old and above.
Ultra loft
An ultra loft bed is 76.5 inches tall and has an under bed clearance of 58 inches.
It’s the tallest loft bed and it’s best suited for teenagers who have limited bedroom space. You’re going to have almost five feet of under bed space for your stuff and possibly a desk.
Low bunk
A low bunk bed is 61.5 inches tall and it usually has a gap of 32.25 inches between the top and bottom bunk.
It’s best suited for two kids aged 8 and above to share each bunk.
Medium bunk
A medium bunk bed is 66.25 inches tall and has a gap of 37 inches between the top and bottom bunk.
Medium bunk beds are great for kids who are 10 years old and above.
High bunk
A high bunk bed is 71 inches tall and has a gap of 41.75 inches between the top and bottom bunk.
This bed is a good option for young teenagers who are sharing a smaller bedroom.
Triple bunk
The tallest of all bunk beds, a triple bunk bed is 92.25 inches tall.
You can use this type of bunk bed if you have three teenage kids that are sharing one room. Triple bunk beds are great for space-saving especially in small bedrooms.
Corner loft
Corner loft beds come in different heights ranging from 50.75″ to 76.5″.
If you don’t know what a corner loft bed is, it’s usually two elevated beds that form an L-shape. Most corner loft beds are made to fit in the corner of smaller rooms and are great for kids and teenagers.
Corner bunk
Corner bunk beds also come in different heights which range from 61.5 inches to 71 inches.
A corner bunk bed consists of four sleeping platforms and is suitable for four kids who share a bedroom. Like a corner loft bed, it’s also designed to fit in the corner of most small-sized bedrooms.
How to choose a mattress for a bunk bed
At this point, you’ve learned about the different bunk bed dimensions and heights. It’s time to choose a mattress but you’re not so sure of what you should be looking for. To help you out, I’ll be sharing the three main factors that you have to consider when choosing a bunk bed mattress.
Height
We usually recommend getting an 8-inch mattress for the lower bunk and a thinner (not more than 6 inches) mattress for the upper bunk. The reason for having a slimmer mattress on the top bunk is so that it won’t be taller than the guard rails. To avoid the risk of accidents, it’s best to stick to a low-profile mattress for your upper bunk.
Body weight
Our general rule is: the more you weigh, the thicker your mattress should be.
A thicker mattress will provide more support and comfort for heavier sleepers. If you’re an average individual, then an 8-inch bed will work just fine. However, individuals over 250 lbs. should opt for a mattress that’s 10-12 inches thick.
Quick reminder: Make sure to place the thicker mattress on the bottom bunk for the safety reasons we discussed in the previous section.
Type of frame
Lastly, the mattress has to be compatible with the type of bed frame you have.
Whether it’s a metal or wooden frame, check its weight capacity first before choosing a mattress. If you want to reinforce your bunk bed frame, you could try adding a bunkie board on top of it.
Check out our best bunkie board list for durable options.
FAQs
Depending on its construction, a bunk bed will usually be 61.5 to 71 inches tall.
Two adults can sleep in a bunk bed as long as its either Queen or King size. Twin or full bunk beds won’t provide enough space for two adults.
Unless it’s used in a college dorm, individuals who 18 years old and above will usually stop using bunk beds.
Yes, you can use bunk beds if you have an 8-foot ceiling as long as the gap between the top bunk and the ceiling is two feet or more.
Conclusion
From the more common twin bunk beds to rarer king bunk beds, you can choose the size that best suits your needs, bedroom space, and budget. Don’t forget to consider the height of your ceiling so you won’t get a bunk bed that’s overly tall. Lastly, it’s important to select right type of bunk bed. Whether it’s a standard bunk bed or a triple bunk bed, get the one that fits you best.
Next step: Read our guide to bed frames for memory foam mattresses. If you have a foam mattress, then you need a bed frame that can properly support it. We tested each brand on this list to make sure that they’re compatible with memory foam.
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