From Single to King: Bed Size Dimensions Broken Down

Written by Nectarsleep Editorial Team

Last updated on Sep 08, 2023

Better Sleep Blog
From Single to King: Bed Size Dimensions Broken Down

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When it comes to choosing the right kind of mattress, we know that support and comfort are the foundations to a great night’s sleep every night, and with a Forever warranty, a 365-night home trial, and a five-layer smart mattress that works with all bed frames, we know we’ve got a winning formula, making your shopping experience a whole lot easier. The only hurdle that’s totally up to you? Choosing the right size for your home and needs.

Thankfully, though, we can lend a hand with that, too. Read on for our easy guide to finding a mattress size that lends you and your loved ones all the comfort needed, without compromising on style and space. Aren’t we good to you?


Super King; Queen; Twin; Double; Small Single—chances are you’ve heard all of these terms bounced around a mattress showroom, or as you’ve been doing your research online. Who knew there could be so many variants? Trouble is, not all of these terms fit our bed frames here in the UK (we’re looking at you, California King!), with a lot of lingo borrowed from our friends across the pond, making it rather confusing when it comes to determining what mattress size you need (not to mention figuring out what bedsheets will actually fit!). So, what dimensions are we actually working with when it comes to finding a mattress that will fit our bed? In Britain, we work with six (yes, really) standard dimensions. So, what size will work for you?

Small Single (75cm x 190cm)

Size is everything—but biggest isn’t always best. A small single is a perfect solution to a less than generous floorplan: think attic spaces and guest bedrooms. This perfectly-formed mattress is also handy for daybeds, perfect for that friend who likes to sleep over last minute (and often)—but you happen to live in a studio. A small single is an ideal transition mattress for children moving from the cot to their first “grown-up” bed, and the good news is that it will comfortably see them through much of their childhood before they look for a little more space in their sleep. A small single can look lost placed in the middle of the room as the narrower dimension of this mattress is designed with limited space in mind; nestled along a wall, you still have room for a bedside table and can create some cosiness with a rug, reading lamp and a few floating shelves—handy for storing those childhood classics to be read before lights out.

Single (90cm x 190cm)

A single mattress is ideal for small guest rooms, children’s and teenage spaces. The slightly longer length of this standard single mattress means it’ll comfortably accommodate a single adult, but the dimensions of this mattress won’t dominate a narrow bedroom. Single mattresses are great space-savers for when more than one child is sharing a room—two small doubles in a bedroom would feel cluttered and cramped, while two single mattresses provide just the right amount of comfort and still leaves you with floor space to play with.

Small Double (120cm x 190cm)

Sometimes (but not always, which is why it’s always smart to double-check those measurements) called a Queen (another borrowed term from the US market), the dimensions of this mattress come in slightly narrower than a standard double, which means that while it can accommodate two people, you might not find a small double an entirely practical solution for any other room than a guest room if you’re not solo sleeping and prefer a little more space when you snooze. But a small double can be a blessing for those narrow box rooms and spaces where you’re looking to allow a little walkway either side of the mattress and not find yourself brushing up against the wall to enter and exit your bed.

Double (135cm x 190cm)

Perhaps your dog likes to snooze between you and your loved one at night, or your youngest child still likes to climb under the covers and join you at the weekend—if you’re looking for a little more versatility and have the room to play with, then a double mattress is a safe bet, providing a little more wiggle room for a more constant use that’s easy to adapt to your lifestyle as it evolves over time. Better yet, the dimensions of a double will work in most moderate-sized bedrooms, so you’re not sacrificing the space of your room for a little more in bed.

King (150cm x 200cm)

If you happen to be tall, and you’re not one for sleeping curled up in the foetal position, then a King size mattress is going to feel comfortable—no one really likes their feet hanging off the end of the bed, do they? Wider and longer than a standard double, the dimensions of a king size mattress really amp up your sleep style with plenty of room for you and your partner. Not got such a royal space to work with, but feel that a king is the best companion to meet your needs? Consider less symmetry in your room with just one nightstand, or opt for tall wardrobe rather than wide dresser that can accommodate all your clothes but won’t eat up valuable floor space.

Super King (180cm x 200cm)

If you’ve got the room and want to make a statement, then a Super King is the ultimate in starfish-spread-sleeping luxury. There’ll be no complaints of hogging space with the generous proportions of this mattress, but if you’re not dealing with an abundance of space in the bedroom, then you’ll find that the dominating appearance of this mattress leaves your space feeling cramped. The super king mattress is a whole foot wider than a king, which means you can roll over – and over – before you even come into contact with your other half: bliss if you or they happen to be something of a restless sleeper. If you're wondering what their sleep position says, it's probably telling you more than you think.

When it comes to considering what size mattress will work for your room, it really is best to take the time to measure your floor space and think about how and when your mattress is going to be used. Think, too, about the positioning of your bed, and what frame you’re looking to match to your mattress. Map out a potential spot and mark the dimensions with some tape on your floor—an instant visual is a great way to picture your future Nectar mattress in your room. If you’ve got space for a super king but fear it’s going to command too much attention in your room, then a floating or open frame can be a great call to keep your space feeling open and inviting.

There’s no right or wrong size when it comes to choosing a mattress, and while space and need should be on your list of considerations when debating between a king or super king, it’s important to remember that, above all, a new mattress should provide you with a lifetime of sleep satisfaction and comfort—and that we don’t need to weigh up and compare. Nectar has you covered. Our mattresses are sure to please you, no matter what size you need. It's not the size of the mattress in the bedroom, it's the size of the comfort in the mattress.