When shopping for a mattress, firmness should be a major consideration. A soft mattress closely hugs the body, while firm beds support body weight more evenly to prevent sleepers from sinking. Beds with medium firmness levels typically combine stable support with a touch of soft contouring.
Some firmness levels meet the needs of different body types and sleep positions better than others, and finding the right one for your situation is essential. Without the proper support, your posture and overall comfort may suffer, leading to pain and poor sleep quality.
To help you buy the bed best suited to your needs, we’ll discuss how to choose the right mattress firmness based on your sleep position, body type, and individual preferences.
David Rubin
Director of Product TestingFind your perfect mattress
We’ve tested hundreds of mattresses to help you sleep better. All it takes is 5 questions.
What position do you sleep in?
Side
Back
Stomach
Back
How to Determine the Right Firmness for You
Determining the right mattress firmness can be challenging, especially for couples. If a bed is too soft for your body weight or sleep style, you risk losing support, which is harmful to your sleep posture. On the other hand, mattresses that are too firm don’t provide enough cushioning and can result in spinal misalignment.
Based on Your Sleep Position
The mattress firmness that best supports you varies based on your sleep position. For example, the best mattress for side sleepers is generally softer than the best mattress for back or stomach sleepers.
Side sleepers typically benefit from softer mattresses because they cradle the hips and shoulders to help maintain spinal alignment. Back and stomach sleepers need less contouring and receive better spinal support from firmer beds with stable surfaces that prevent sinkage.
Based on Your Body Type
Mattress performance is partially dependent on your body type. Softer mattresses generally aren’t as durable as firm models and have a tendency to sag, so they often aren’t the best option for people who weigh more than 230 pounds. These sleepers need a firmer surface and a sturdy comfort layer to maintain stability.
However, softer mattresses provide a comfortable, supportive sleep surface for many people under 130 pounds. People weighing between 130 and 230 pounds often prefer beds with a medium to medium firm rating.
Our Firmness Scale
We use a 10-point rating scale to evaluate firmness when testing beds. Mattresses with 1 through 3 ratings are considered extra soft or soft, which means they have a plush feel and minimal pushback. A 4 corresponds with medium soft on our scale, while 5 and 6 are medium and medium firm, respectively.
Our 7 through 10 ratings are firm or extra firm, ranging from beds that offer significant pushback to a nearly rock-like feel. Mattresses at extreme ends of the scale are rare, with most falling somewhere between 3 and 8.
When ascertaining the firmness level that’s right for you, it’s crucial to take your body weight and build into account. Sleepers weighing less than 130 pounds put less pressure on a mattress and require more cushioning, so they often prefer a softer bed. People over 230 pounds typically need firmer support and denser comfort layers.
In cases where couples have firmness preferences at opposite ends of the spectrum, a medium feel may offer a compromise that best meets their separate needs. Another option is a split mattress, which allows couples to customize the firmness level of each half of the bed.
What We Recommend
Our recommendations for mattress firmness are based on our years of experience in the sleep industry and intensive testing of sleep products, as well as general preferences that we’ve found hold true for most sleepers.
Sleepers Under 130 Pounds | Sleepers 130-230 Pounds | Sleepers Over 230 Pounds | |
|---|---|---|---|
Side Sleepers | Soft (3) to Medium (5) | Medium Soft (4) to Medium (5) | Medium Firm (6) to Firm (7) |
Back Sleepers | Soft (3) to Medium (5) | Medium (5) to Firm (7) | Firm (7-8) to Extra Firm (9) |
Stomach Sleepers | Medium Soft (4) to Medium Firm (6) | Medium (5) to Firm (7) | Firm (7-8) to Extra Firm (9) |
How Can I Tell if My Mattress Is Too Soft or Too Firm?
If you aren’t comfortable or don’t feel supported by your bed, it’s likely too soft or too firm. A mattress that’s too hard doesn’t cushion the sleeper at pressure points, causing discomfort and spinal misalignment. A mattress that’s too soft can result in excessive sinkage and poor sleep posture.
It’s normal for brand-new beds to feel slightly off at first, so give it time. After allowing for an adjustment period, you should be able to tell relatively easily if the mattress is too soft or firm for you.
Should You Sleep on a Firm Mattress?
While mattresses with a firm feel provide comfort and support to a range of sleepers, this firmness level doesn’t work for everyone.
Stomach and back sleepers often require a firm mattress to achieve good spinal alignment. However, firm mattresses don’t provide much contouring or pressure relief, so side sleepers often prefer plusher models.
Durability is a significant benefit of firm beds. Soft beds may weaken and collapse over time, but firm mattresses stand up well under weight, even for people weighing more than 230 pounds.
Firm Mattress
Pros
- Supportive enough for stomach and back sleepers, as well as people over 230 pounds
- Creates a buoyant feel with even weight distribution and minimal contouring
- Increased durability
- Often sleeps cooler than a soft bed
Cons
- May not provide enough cushioning for side sleepers or people under 130 pounds
- Lacks conformity to ease pressure points
- Typically not recommended for people with certain conditions affecting the lower back, such as scoliosis or arthritis
Is a Firm Mattress Better for Your Back?
A firm mattress can be good for your back, but its performance ultimately depends on your body type and favored sleep style.
The best way to avoid back pain is to sleep with proper posture. If you’re a stomach sleeper, a firm mattress may help prevent back pain by keeping your abdomen from sinking into the mattress, which can misalign the spine and create muscle strain. People with scoliosis or arthritis may prefer a softer mattress due to the extra cushioning.
Should You Sleep on a Soft Mattress?
Featuring plush, enveloping surfaces, soft mattresses accommodate a variety of sleepers. However, a soft bed isn’t the perfect match for every sleep position or build.
Mattresses on the softer end of the firmness scale typically provide above-average pressure relief, which is a benefit to side sleepers who like a contouring feel in the hip and shoulder areas. Back sleepers may enjoy some light conforming but likely won’t find an overly soft mattress supportive, and stomach sleepers almost always prefer a firm bed.
Softer mattresses typically aren’t as durable as firmer beds, so they require more frequent replacement.
Soft Mattress
Pros
- Extra cushioning responds to body weight and conforms at pressure points
- Great for most side sleepers
- Best option for those who like to sink into their bed
Cons
- Not the best choice for most stomach sleepers
- Tends to sag over time and lacks support for those weighing more than 230 pounds
- May sleep hot when not specifically designed for breathability
Is a Soft Mattress Bad for Your Back?
A soft mattress can help prevent back pain if you sleep on your side and require good pressure relief. However, if you sleep on your back or stomach, it may not support your spine adequately and may contribute to back pain instead of reducing it.
Back and stomach sleepers with back pain should consider a medium firm mattress, which offers a combination of support and gentle conforming. Some models include enhanced lumbar support designed to help ease lower back pain.
About The Author
Certified Sleep Science Coach, Director of Product Testing
David is a Certified Sleep Science Coach with a lifelong passion for well-being and health optimization. His interest in sleep developed with the arrival of his son, when sleep suddenly became a precious commodity.
- POSITION: Side Sleeper
- TEMPERATURE: Hot Sleeper
- CHRONOTYPE: Lion
Ask the Sleep Doctor
Have questions about sleep? Submit them here! We use your questions to help us decide topics for future articles, videos, and newsletters. We try to answer as many questions as possible. You can also send us an email. Please note, we cannot provide specific medical advice, and always recommend you contact your doctor for any medical matters.
