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The only beds styles with two entirely different names, it’s no wonder why people get a little bit confused about Twin and Double beds. We’ve covered a lot of bed sizes on this site but we have yet to uncover the mystery why Twin beds and Double bed are also called Singles and Fulls. Well, today’s the day we find out (and then some).
Difference between Twin vs. Double Bed size
| Bed type | Twin/Single | Double/Full |
|---|---|---|
| Dimensions (inches) | 38" x 75" | 54" x 75" |
| Bedding | Easily available | Easily available |
| Bed Frame | Easily available | Easily available |
The main difference between a twin and a double bed is their width – while both bed sizes are 75 inches long, the twin bed measures 38 inches across and the double bed is 54 inches wide.
This gives double beds an edge over single beds, with that extra 15 inches giving room to an extra sleeper, albeit someone not very tall or plus-sized (but hey, cuddles are always a good thing). A single bed can usually only occupy a single sleeper.
What is a twin mattress?
Twin beds or twin mattresses are also called single beds, depending where you find yourself in the world. In the United States, the term ‘twin bed’ is often used whereas in the other parts of the world, ‘single bed’ is the more common terminology.
But why is it called a “twin” bed when it can only fit one sleeper, you might ask?
Well, in the olden days (not really – think ’40s or 50s), hotels would offer rooms with two single beds, referring to them as a twin room and the terminology just stuck. So if you’re going bed shopping, keep in mind that a twin bed and a single bed have the exact same dimensions.
Although adults can sleep fairly comfortably on a twin bed, more often than not you can find twin beds in children’s rooms as a twin bed is usually used by kids as a transition bed from a baby bed such as a cot or a crib. It’s the perfect mattress size for kids.
Twin mattresses and their longer counterparts, the twin XL mattress, are also often used in bunk beds or trundle beds in dorm rooms or camps (they are a great mattress for college students). The twin XL mattress is also a good choice for taller sleepers who are also single sleepers.
But single beds don’t really offer much space in terms of sleeping area (no matter what Bob Marley says), and if you share your bed with a partner or a pet or are the type of sleeper who likes to move around a lot, 38 inches isn’t really going to do much for you.
Pros
- Gives rooms more floor space
- Can fit into any room
- Bed frames and compatible bedding are inexpensive and widely available
- Helps kids transition into a big kid bed
- Can sleep either kids or adults
- Often used in bunk beds
Cons
- Does not offer enough personal sleeping space for those who share a bed with a pet or a partner
- Not suitable for taller individuals or heavier-set sleepers
- May not look right in the bigger-sized bedroom (aesthetics and symmetry are very important to some)
What is a double bed mattress?
As we’ve mentioned above, double beds measure 54 inches wide and 75 inches long and can offer a whole lot more sleeping space than a twin bed can.
Also called a full bed (no fun origins story behind the name sadly, see our double vs. full comparison for more details), double beds are so named because they can technically sleep two people instead of just one. But single sleepers also often go for a full-sized bed over Queen beds (which is 80 inches long and 60 inches wide) as it offers ample space for sleeping without taking too much room in a bedroom. Those who live in studio apartments usually opt for a double bed.
It is also fairly easy to find matching bedding and bed frames for a double mattress although of course, they will be slightly more expensive than those of a twin bed. Keep in mind that as bed sizes go up, so do the prices. The same goes for both bedding and bed frame. But both double beds and twin beds can be had for a fraction of the price of say, a California King bed or other King-sized beds. See our double vs. queen article to see how it compares to the most popular mattress size.
Although anyone can sleep on a double size bed, they may be a bit too large for children’s rooms. Double beds are also often used in a guest room where they can also offer more space in case you need to maximize your space into a home office or even extra storage.
Both full-sized beds and twin beds can come in a variety of different mattress types to choose from such as latex, memory foam and innersprings.
Pros
- Can sleep two average-sized people comfortably (or you and a pet)
- Comes in many different bed styles
- Bedding and bed frames are easy to find and fairly inexpensive
- Still offers enough floor area compared to other bigger bed sizes
Cons
- May be slightly more expensive than twin beds
- May not offer enough sleeping space for plus-size couples
- May not offer enough space for taller individuals
How to choose between a double and twin mattress
If you find yourself a little bit undecided on whether to opt for a double bed or a twin bed, the following are the things you should consider:
Sleeper size
As we’ve said, while a twin bed can technically fit a fully grown adult, those who are taller, heavier-set or just want a bit more room to move around may not be able to get a good night’s sleep.
Double beds can offer a lot more sleeping space for a single sleeper.
Room size
Both twin and double beds have the same length with a 15-inch width difference and both can fit into most average-sized bedrooms. That said, a twin bed can offer a lot more floor space than a double bed so if what you need is space maximization, a twin bed is your best bet.
Sleeping with a partner
Although sleeping all cuddled up on a twin bed with partner sounds infinitely romantic, it can get uncomfortable real fast, especially if you share the bed day in and day out. If you share a bed with a partner or even a pet, double beds are the way to go.
Price
Both a twin and double bed are not too pricey, depending on the brand you plan to purchase from but double beds are slightly more expensive than twin beds. The cost of a twin mattress is much less than any other mattress size. If you’re looking for a more budget-friendly option, best to choose a twin bed.
Ease of moving
The bigger the bed, the harder it is to move and while both twin and double beds are not exactly what you would call oversized beds, a twin bed would still be much easier to transport than a double bed.
If you are somewhat of a nomad and like to move around a lot, it would be easier and more convenient to choose a bed that’s smaller and easier to move. Remember, you would need to dismantle (if it needs it) and move the bed frame too.
Cost of bedding
Bedding for both twin beds and double beds are easily found but prices may vary depending on the brand. But just like bed sizes, the larger the bedding, the more expensive they can be. If cost is no trouble and you want more space, opt for a double bed.
FAQs
Two twins do not make a double bed. Although they are of the same length (which is 75 inches), a double bed is only 15 inches wider than a twin bed. Two twin XL beds (39″ x 80″), however, when joined together, make up the same dimensions as that of a King bed.
Two people can fit comfortably on a double bed, provided that they are both not too tall or plus-sized.
A double bed is not the same as a twin XL bed. Although a twin XL bed is longer than a double bed, a double bed is wider.
Conclusion
The difference between a twin bed and a double bed may only be 15 inches but those 15 inches can determine whether it is the right bed size for you or not.
If you’re looking to save on both space and money, opt for a twin bed but if you need more space to move around while you sleep, a double bed would be best for you.
Next step: Read our Nolah mattress review. If you’re looking for a twin-sized mattress, Nolah is a brand to consider. We go over the pros and cons so you can decide for yourself if their mattresses are right for you.
Michelline loves nothing more than a cozy bed, with a stack of books at her side. She loves getting lost when she travels, can bake an entire British afternoon tea from scratch, is obsessed with all things analogue and does calligraphy on the side. She currently suffers from mild insomnia and is more than happy to be your guinea pig, so you won’t have to go through all the trouble of finding out what works best for you.
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