Firmness is the thing people ask about most before buying a mattress, and also the thing most often misunderstood. There is no mattress that is best for everyone. There is one that suits your sleeping position and your weight, and that is what this guide covers.

Start with how you sleep

• Side sleepers: your shoulder and hip take the most pressure, so a slightly softer mattress lets them sink in and eases it. Look at pillowtop or memory foam.
• Back sleepers: you need balanced support that keeps your spine straight. Medium to medium-firm suits most people.
• Stomach sleepers: your hips should not sink, so a firmer mattress works best.
• Combination sleepers: choose medium. It copes well with every position.

Weight makes a difference

A lighter person feels a mattress as firmer than a heavier person does on the same mattress. If you weigh less than average, a slightly softer mattress gives you the same comfort. If you weigh more, firmer and taller mattresses hold their shape for longer.

Firmness is not support

Many people think a hard mattress means better back support. Real support means your spine stays straight, whether the mattress is firm or soft. A very hard mattress can press on the shoulder and hip, and a very soft one can let your back curve.

If you are not sure

• Answer the questions in the Mattress Quiz and we will rank the mattresses closest to how you sleep.
• Compare two or three mattresses on the mattresses page and look at the firmness from 1 to 10 on each product.
• Contact us and we will help you choose before you buy.