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What Is the Size of a King Size Mattress?

How Wide Is a King Size Mattress?

150cm (5ft) wide.

How Long Is a King Size Mattress

200cm (6ft 6in) long.

How Deep Is a King Size Mattress?

The depth of our king sized mattresses differs by model. However, they range from 24cm (Beulah 1000 No-Turn Mattress) to 33cm (Rodmarton Pillowtop Wool Mattress). We've listed them in the helpful chart below:

Mattress Model Approx. Depth
Mattress Model Approx. Depth
Beulah 24cm
Hebridean 28cm
Standen 29cm
Rodmarton 33cm
Blackwell 31cm
Lindisfarne 30cm
Holcombe 32cm

Which Is the Best King Size Mattress to Buy?

Here, at Woolroom, we have two king size wool mattress collections: Classic and Artisan.

Our Classic: models provide an affordable entry to the world of wool sleep. Individual pocket springs, micro coils and super soft Wool ID® traceable British wool work together to give you all the support you'll need during the night.

Our Artisan*: range features mattresses hand-crafted by the industry's best. Each is carefully filled with a blend of Wool ID® traceable British wool, cotton, cashmere and silk. Hand-tied pocket springs boost breathability and provide precision contouring, while hand-stitched sides create edge-to-edge support, so there's more space for you to really make yourself comfortable.

*Available in soft, regular and firm tensions.

Sleeping Positions

If you're a side sleeper, you'll want a king size mattress with lots of cushioning. You'll probably find our soft and regular tensions to be the best option - you'll get all the spinal support you need while being able to able to sink slightly into the mattress.

Sleep on your back or front? Your spine and joints will likely experience more pressure as a result, so, our firm tension will most likely suit you best - as it provides increased support.

Looking for some extra help on how to choose the right king mattress for you? Read our guide on 'How to Choose the Right Mattress'.

How Often Should You Rotate a King Mattress?

We recommend you turn and rotate your mattress weekly for the first 12 weeks***. You should then only need to turn and rotate it once every three months.

***Not applicable for Beulah 1000 No-Turn Mattress, or the Rodmarton Pillowtop Mattress.

Can a King Size Mattress Fit On A Double Bed?

No, as king sized mattresses are much wider than double beds. This would leave your mattress hanging over the edge of the bed and potentially risk it tipping when you sit on the edge. If you're looking for a mattress to fit a double bed, don't worry - you'll find all the fantastic options displayed above in our Double Mattresses range.