Advertiser Disclosure
Firm Vs. Soft Mattress | Complete 2021 Guide

Firm Vs. Soft Mattress | Complete 2021 Guide

Read our detailed guide for an explanation of soft vs firm mattresses.

With a near endless selection, understanding the basic components around firm vs. soft mattresses assists in narrowing down the field of contenders to choose from. While a firm mattress is more rigid and a soft mattress compresses more easily, the characteristics of the mattress make a difference during hours of sleep. In this guide, we’ll dive into the pros and cons of each mattress firmness and explain who we think each one works best for.

The Slumber Yard team has personally tested hundreds of mattresses.

Answer 5 easy questions and we'll help you find the perfect mattress!

Plush vs Firm Mattress Introduction

Mattresses described as “plush” or “soft” feel softer on the sleeping surface, and provide a cushion and cradle effect for sleepers. One of the primary benefits of a soft mattress is pressure point relief.

Mattresses described as firm, on the other hand, focus more on support. While sleepers who prefer plush mattresses sometimes describe them as stiff and uncomfortable, firm beds create more neutral spinal alignment for stomach and back sleepers.

Within this guide, we’ll review the different firmness level options you commonly have available to you when choosing a mattress, and reveal the pros and cons of each one.

Mattress Firmness Levels: Soft, Medium, and Firm 

While mattress descriptions generally begin with the words “soft” or “firm.” In truth, far more subtlety exists in terms of the degrees of softness or firmness. In other words, the firmness (of softness) of a mattress really falls into a spectrum.

Here’s a look at the proprietary Slumber Yard spectrum for the Original Casper mattress.

Firm vs soft scale for the casper mattress
Firmness scale for the popular Casper mattress

Additionally, soft mattresses and firm mattresses each adhere to different sleep styles. For example, a side sleeper puts pressure on shoulders, elbows and hips. By sleeping on a softer mattress like Casper Nova, these pressure points are cradled and cushioned as the mattress contours to the curves of the body.

By the same token, the support given from a firm mattress works best for stomach and back sleepers. While a soft mattress drops the body down, a firm mattress provides the support needed to keep the spine in alignment.

Finally, mattresses described with medium firmness combine elements of a soft mattress to offer pressure relief, without compromising support. The idea, really, is to offer the best of both worlds.

Is A Firm Mattress Better?

The beneficial elements of a firm mattress, as we’ve mentioned, centers on reinforcement for your back and spine. Great for stomach sleepers, back sleepers, and heavier individuals who are looking for more support, firm mattresses maintain proper spinal alignment.

Maintaining spinal alignment prevents tightened muscles and back pain, which is especially important for people who may suffer from a condition like Sciatica. With ingredients for a restful night’s sleep, firm mattresses provide sleepers with a bright-eyed refresh.

What’s more, the support offered in firm mattresses add to the comfort level for sleepers with higher body weights. Instead of excessive compression as a heavy individual lies down, a firm mattress compresses less because of the supportive design.

Firm beds can also be cooler than soft mattresses because you sit more on top of the mattress, rather than sink into the comfort layers.

Cons Of A Firm Mattress

While a firm mattress offers the benefit of support, mattresses designed with excessive support features amount to too much of a good thing. Really firm mattresses may be too much for some sleepers, especially if you switch positions here and there during the night.

Although some individuals benefit from hard-support firm mattresses, many sleepers need at least a little bit of cushion to achieve comfortable, restful sleep.

Benefits Of Purchasing A Soft Mattress

For sleepers who enjoy a mattress that cradles their body, soft mattresses provide a deep cushion hug or a traditional deep contour feel, such as what you get from memory foam mattresses. The bed acts to cradle and cushion throughout the night, regardless of your sleeping position. This firmness level is really pressure relieving, which can be helpful for those who suffer from arthritis or joint pain.

Especially for individuals with body weight on the lower side of the scale, a soft mattress is worth considering as a firmer mattress style provides less give than softer mattresses do.

Why You Might Pass On A Soft Mattress

The primary drawback of a soft mattress goes to the support it offers. More precisely, the softer a mattress is, the less support you’re going to get. This might not be ideal for somebody who weighs over ~230 lbs, because they need a mattress that proves to be durable, and supportive under more pressure.

The sinkage that accompanies extremely soft mattresses creates body misalignments that can create uncomfortable sleep and general body achiness for those who aren’t strict side sleepers with petite to average body types.

When To Buy A Mattress With A Medium Firmness 

A mattress designed with a medium firmness level essentially establishes a compromise between support and pressure relief. As mattresses with a medium level of firmness provides an optimal design for an estimated 80 percent of sleepers, individuals looking to purchase a new mattress may want to consider their options in this mid tier range.

As mattresses with a medium firmness offer benefits of both soft and firm mattresses, a medium firmness works really well for combo sleepers who don’t conform to a strict sleeping position. With a medium mattress, combination sleepers maintain pressure relief while lying on their side while maintaining spinal alignment while lying on their back or stomach.

If you’re petite or under around ~200 lbs, we especially think you can get away with a mattress with a medium firmness regardless of your sleeper type because it’s so balanced.

Additionally, mattresses with a medium firmness act as a kind of compromise for couples with different sleeping styles. By combining features that provide both cushion and support, a mattress in the medium firmness category works to provide comfort and restfulness all the way around.

How Your Weight Affects A Bed’s Firmness Level

Fundamentally speaking, buying the right mattress really requires consideration of body size. Across the board, smaller individuals experience mattresses as firmer while heavier people experience mattresses as softer.

Very simply, weight determines the degree to which the body lays atop the mattress as well as the degree to which it sinks into the mattress.

The variables play into the soft, medium, firm mattress spectrum. We recommend a soft mattress for light- and average-weight people; a medium firm mattress for light, average and heavy people; and firm mattresses for heavy people who want a mattress with more support.

Some mattress manufacturers are stepping into a heftier niche with development of specialty beds for higher weighted single-sleepers, as well as those with a sleep partner. These specialty beds offer weight limits into the 500- to 1,000-pound range.

Other Considerations When Choosing Firmness

Besides weight, sleep style plays a big factor in determining the ideal softness or firmness of a mattress.

Sleeping Style 

Side sleepers, for example, put pressure on the shoulder, elbow, hips and sometimes the knees. In these cases, a firmer mattress creates more pressure while a softer mattress relieves the pressure.

For stomach and back sleepers, issues center more on spinal alignment. For these sleepers, a softer mattress sinks the body out of alignment through a lack of spinal support. A firmer mattress, on the other hand, provides the spinal support necessary to awaken rejuvenated.

For sleepers who often experience low back pain, or sleepers who suffer from arthritis, restful sleep doesn’t come easily.

Health Conditions

Sleepers with low back pain or arthritis might find relief by choosing a really accommodating mattress that cradle’s their pressure points. Addressing low back pain requires emphasis on support and spinal alignment. Arthritic joint pain, stiffness, swelling and tenderness requires support as well as pressure relief.

layla mattress review cover soft and firm side,layla mattress review firmness softness of the bed
Layla has both a soft side and a firm side

Interestingly, fluctuations in the degree of back pain or arthritic flare-ups could also change mattress needs. One solution is a flippable mattress that offers alterations in firmness with its flippable design such as the Layla Hybrid. One side of the mattress rates as a medium soft mattress while the other side rates as a firm mattress.

Sleeping Arrangements

When you sleep alone, you only have to worry about your bed being suitable for your needs. When you add a significant other or loved one into the mix, you should be mindful of their sleeper and body type as well to find a reasonable middle ground.

As we mentioned before, if your partner is a different sleeper type than you, consider getting a mattress with a medium firmness level. Additionally, if your partner has a heavy body type, you may want to opt for a firmer bed or a hybrid mattress to achieve a more supportive feel.

Firm Or Soft Mattress: Verdict

Finding the right mattress for a comfortable and restful sleep comes with no shortage of options. As manufacturers develop a range of products that go from very soft to extra hard, consumers in the market for a new mattress do well to understand the personal elements that play into the soft-to-firm spectrum.

Beyond how comfortable a mattress feels when initially going to bed, the real test of whether a mattress is a good fit depends on the level of refresh and rejuvenation felt on waking. Whether too soft or too firm, sleeping on the wrong mattress results in poor sleep and an achy body. Make sure you’re taking your sleeper type into consideration, body type, and the needs of others who might share a sleeping space with you.


Is it better to sleep on a hard or soft mattress?

Body type and sleeping style determine whether a hard or soft mattress offers better sleep.

Will my weight affect how a mattress feels?

Body weight determines how much sink the mattress offers. An individual with a lower body weight stays more atop a mattress while an individual with a higher body weight sinks down more into the mattress.

What firmness is best for back sleepers?

Back sleepers require the support of firmer mattresses for proper spinal alignment.

What firmness is best for side sleepers?

Side sleepers require the cushioning of a softer mattress for pressure point relief.

What is a double-sided mattress?

A double-sided mattress essentially acts as two mattresses in one. Each side provides a slightly different firmness level, allowing sleepers to adjust the mattress with fluctuations in the body or prefrences.