Sleep is the most important thing in our lives, no doubt about that. We spend a third of our lives sleeping. But how many of us actually sleep well?

A mattress is the most important element in a good night’s sleep.

Not only does it have to support your body but it should also support your spine and help you relax. I am sure you are aware of all the benefits of a good night’s sleep. It helps us function better, improves our metabolism and helps us stay focused.

However, we do not always get what we want from our mattress.

It might be that the mattress is too soft or too hard, or perhaps you lack support in certain areas of your body (this is usually seen as back pain).

If this happens to you then you might consider getting a new mattress.

The mattress industry has boomed over the last decade, with new types of mattresses coming on to the market every year. It can be difficult to know which is the best for you.

You could go into a store and try them out, but if you live somewhere where there are no stores nearby then you will have to order one online and wait for it to be delivered.

When shopping for mattresses online there are many different sizes available from twin to king size plus many other ones in between. It can be confusing trying to decide which size to get for your bed and which one will be best for you.

To help you choose we have put together this guide on the sizes available and how they match up with bed sizes so that now you can easily find what is best for your bed whether it is a twin or larger king size bed.

We will also discuss which sizes are best for certain situations and who they would suit best (for example, if you are tall, short, overweight etc.). 

We will also look at whether it matters if your mattress has a different length or width to that of your bed frame and how this affects comfort levels when lying on it (and even when getting in or out of bed!).

Here’s The List of The Mattress Sizes

Single (145cm x 190cm)
Double (135cm x 190cm)
King Size (150cm x 200cm) or Super King Size (180cm x 200cm)
Extra Long Single (190cm x 200cm) or Extra Long Double (200cm x 200cm)

Single (145cm x 190cm)

Single is the smallest standard mattress size available. It is the perfect choice for those who are looking for a single bed to fit a tight space, or as an alternative to a larger double bed.

It is also a good choice for those who are not tall and prefer to be able to stretch out slightly on their bed.

Double (135cm x 190cm)

Double beds are the most popular mattress size in the UK. They are suitable for single people, couples and those who like to spread out while sleeping. 

Double beds are available in several styles, including styles with headboards and footboards that make them look like king-sized beds.

King Size (150cm x 200cm) or Super King Size (180cm x 200cm)

King sized mattresses can be used in place of two single mattresses or one double mattress. King size mattresses come in single, double and super king sizes. 

The super king size offers more space for couples that like to spread out or sleep in different positions at night. Most new-build houses have room for a king sized mattress, but if you have an older house you may need to consider building work before purchasing one of these large mattresses.

Extra Long Single (190cm x 200cm) or Extra Long Double (200cm x 200cm)

These sizes are suitable for taller people who like to stretch out when they sleep, but who do not want a king sized mattress. They are also useful for people who want more space in their bedroom than a standard double bed provides. 

Extra long mattresses can be used as the only mattress in your bedroom if you have the space for it, or they can be used as an alternative to a king sized mattress if you don’t have room for two large beds next to each other in your bedroom.

How to pick the best mattress sizes?

When you are buying a mattress, there are many things to consider. The biggest mistake people make is that they focus only on the size of the bed, but forget to check the mattress sizes. If you do not pay attention to the mattress sizes, it might not fit!

The size of a mattress is determined by three important factors: the bed frame (or base), the type of mattress and the thickness of the mattress. The measurements of a mattress are always given in inches.

Here you will find all you need to know about different mattress sizes, how to pick the right one for you and how these different sizes fit into different beds.

Mattress Sizes: Length & Width (Mattress Width Vs Length)

The size of a mattress is determined by three important factors: the bed frame (or base), the type of mattress and the thickness of the mattress. 

All these three factors together determine how big your mattress is going to be. The measurements of a mattress are always given in inches. In order to decide which one suits you best, here are some tips on how to pick it:

1 - Bed Frame – 

The size of a bed frame will usually dictate what size you should buy. Usually, if you have a queen-size bed, then your ideal choice would be a queen-size bed, but this does not apply in all cases and is just a general rule. 

If your bed has rails, then it would be important that your new mattress fits those rails before buying it, as most frames will not allow for bigger mattresses to be placed inside them; otherwise it would be too narrow for them. 

While for king-size beds, if your bed has no rails on top or bottom, then it should be ok if you put any size inside; however if your bed has rails on top and bottom then it should be taken into consideration as well. In this case you should make sure that both sides fit inside otherwise they may not fit at all. 

Finally, we have single-size beds; they are very convenient as they can be placed inside any frame without any problem whatsoever; however note that most frames will not allow for king-size mattresses to fit inside them (unless there is enough room between the posts). 

So if you have a single-size bed, then there is no wrong or right option when choosing your new mattress; ultimately it comes down to your personal preferences and needs. 

2 - Type – 

Depending on what type of mattress you prefer (innerspring or foam), there are certain specifications for each one and some common guidelines for choosing between them like: If you like firm mattresses , then choose an innerspring one as they tend to be firmer than foam ones; however note that even innerspring mattresses do come in different firmness levels.

 If instead you prefer softer ones , choose a foam mattress as they usually come with softer comfort layers than innerspring ones. Lastly, if you want something in between , priority should go towards foam mattresses as they tend to offer more comfort than innerspring ones while still being firm enough. 

3 – Thickness – 

As stated before, another factor that determines what size your new mattress will be is its thickness. 

This specification refers only to its height and not its length or width; therefore take this into consideration when choosing what new size you want. 

For example: If you want something extra thick , select an extra-firm innerspring model or an extra plush foam model as these tend to be thicker than others. However note that both types can come with different firmness levels.

Lastly, if your preferred choice is something thinner , then choose from medium innerspring models or standard foam models as these will usually have thinner comfort layers ; also note that even though they are thinner , their comfort layers can still vary quite significantly depending on what company makes them and what level of padding they use within them. 

4 – Weight Capacity – 

This specification refers only to how much weight its comfort layers can support before sagging occurs. 

Note that this number will vary greatly depending on what type of comfort layer material was used within each model along with other factors such as its density and composition among others; therefore take this into consideration only if weight capacity matters to you personally or if its specifications were listed within their description online so that way there won’t be any misunderstandings. 

5 – Mattress Thickness –

This measurement refers only to how thick or thin each model’s comfort layers are regardless of their material used within them along with other factors such as their composition or density among others. 

Note that most mattresses available today come with at least 7 inches worth of padding behind their comfort layers so unless otherwise specified , ignore this specification entirely when shopping around. 

6 – Price – 

Last but not least comes price ; while price matters less than other factors when picking out your new model.

Most people still care about it so we included it here nonetheless; however note that higher prices don’t automatically mean better quality ; instead look at reviews written by customers who have actually slept on each model personally before making any final decisions regarding its quality because ultimately price doesn’t matter much when picking out a new model once everything else has been considered since quality mattresses do not cost an arm and leg anyways!


Mattress sizes also known as the bed sizes, mattress dimensions, mattress widths and mattress lengths, the mattress sizes are a set of dimensions that denote the physical size of a mattress. 

These sizes are most commonly used in the U.S.A. and are also used in other parts of the world. The most common sizes used in mattresses include the Twin, Queen, King and California King.

The mattresses are measured in inches and can be anywhere between 39 inches to 84 inches wide and anywhere between 60 inches to 84 inches long. 

The standard mattress size is 60” x 80” but there are several other sizes that are used for various purposes.

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