Mattress Sizes and Dimensions - 2021 - Milemont

Mattress Sizes and Dimensions

Twin XL. Full. California King. What does this jargon mean?

I bet you were just led to this post by entering into Googlewhat are the dimensions of a full-size mattress”, or perhaps it was a twin XL or queen? Either way in this blog post you will know exactly what the mattress sizes and dimensions are for every mattress variety in The United States.

To keep matters simple here is the quick answer in table form. Further below I elaborate on the differences between sizes and what size mattress is optimal for couples, pets that like to sleep at the bottom of your bed, and extremely tall teenagers that just have a small bedroom.

Mattress SizeDimensions Inches (Width x Length)Dimensions CM (Width x Length)
Twin38” x 75”96.52 x 190.5
Twin XL38” x 80”96.52 x 203.2
Full54” x 75”137.16 x 190.5
Queen60” x 80”152.4 x 203.2
King76” x 80”193.04 x 203.2
California King/Cal King72” x 84”182.88 x 213.36

When it comes to the mattress and mattress topper size the length and width are standardized, meaning that the size is pretty much universal. Nevertheless, the thickness amongst manufacturers is variant. Also, not all manufacturers follow the same sizing. The above table is a general guideline that the large mattress manufacturers and Milemont adhere to. Always check firstly the mattress size and bed frame size ensuring compatibility.

Next, let me briefly explain some of the benefits and ideal uses of the different-sized mattresses.

Twin Size

The twin bed is a classic single bed, that is most commonly found in children’s rooms or the spare guest bedroom. At 38” x 75” it’s the perfect size for kids once they move out of their crib. An added bonus with a twin bed is it will last a few years before the kids become teenagers and you start seeing sudden growth spurts. A twin-size bed is also extremely useful for the small spare bedroom, and or bunk beds. To still have maximum comfort the optimal mattress thickness should be in the 8-12” range. 

Twin XL

When you hear the twin XL size (38” x 80”) this just means a slightly longer single bed. The twin XL is perfect for teenagers that are taller and need that extra 5 inches. This is especially true if your children sleep on their back or stomach as they will be fully extended with feet dangling off the mattress. A Twin XL is also a great addition to a teenager’s room when unfortunately the space is too small for a full-size bed. 

Full Size

A full-size mattress is 54” x 75”, and in some countries such as the UK, it is sometimes referred to as a double bed. The full-size mattress is perfect for a standard-sized room where you want to optimize the space available and if the bed is just for one person. A full-size mattress can, of course, accommodate two adults but if the sleepers are over 6 feet, this mattress might be a bit small if you sleep on your back fully extended. 

Queen Size

Welcome to the queen-size mattress. At 60” x 80”, it is the most purchased mattress size on the market. The queen-sized mattress is perfect for couples with ample space. A queen size mattress and bed frame will fit well in most standard-sized rooms. With the popularity of the queen-size mattress, you are also spoilt for choice when it comes to bedding. Think soft silky sheets or luxurious Egyptian cotton. With the queen-size mattress, there is even enough room for the kids to wander in for a cuddle on a weekend morning, or perhaps to sleep in the middle?

King Size

When we talk about the king-size mattress we think spacious and luxurious, at 76” x 80” it most certainly is! With the extra 6” width compared to the queen size, having children sleeping in between parents becomes easier. Also if you love to have your pet sleep at the bottom of your bed then there is ample space for them too. A kingsize mattress really enables the sleepers to spread out and stretch in comfort. 

California King

For our last mattress option, I bet you are wondering why the king-size width is greater than the California King? At 72” x 84” the California king-size mattress loses 4” in width and adds it to the height. This is great for those with standard-sized rooms wanting a longer bed but still offering plenty of room horizontally. The California kingsize mattress is the perfect choice for those in the population that are taller.

Final Thoughts

When it comes to picking a mattress there are many factors affecting your decision. Knowing the mattress sizes and dimensions help aid that decision. In addition, when buying a mattress there are other factors to consider such as price, mattress thickness, material, and firmness/comfort preferences to name a few.

I hope this mattress sizes and dimensions blog piece has helped you make a more informed decision. Please leave a comment below on what mattress size you will be buying. Thanks for reading.

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