What position do you sleep in?

This is perhaps the most important factor that will determine your ideal firmness. Side sleepers usually need a firmness in the 3-6 range. Stomach in the 5-7 range. And back in the 4-8 range. If you sleep in multiple positions try to find a balanced level of firmness that hits both needs.

How heavy are you and what’s your body type?

Your body type and weight is also a major factor. If you’re very large you will generally need a thicker mattress that provides better deep compression support. Additionally, very heavy sleepers may find that softer mattresses create too much sinkage due to the increased weight and pressure. Lighter sleepers typically engage more with the top layers and less with the core and base layers. Look for mattresses that have top layers that meet your firmness desires.

Firmness isn’t support

Don’t forget that support and firmness are not the same. You can find a mattress with great support that’s still soft and meets your feel and pressure relief needs.

 

Majority rules

If you’re not sure what firmness to try I recommend going for something in the 6 out of 10 range. This is by far the most common mattress firmness available and for good reason…80% of sleepers prefer a mattress in the 5-7 out of 10 range. If you’re not sure where to start, try a medium feel.

Be careful with soft mattresses

Many times my readers see the word “soft” and gravitate towards that. I would caution against this. Soft mattresses can be perfect if your preference and needs draw you to that. However, these are also the most returned mattress across the industry by far. Many sleepers buy a soft based on the name alone only to find out that soft is actually way too soft. Mattresses in the 3-3.5 range are best for side sleepers. Most other sleeping styles will find them uncomfortable. Additionally, if you’re over 200 pounds you may find that these mattresses create too much hug.