Who it's for: We like this bed for side sleepers because the zoned support springs help hold up your hips but the “marshmallow-y” surface keeps things comfy for your joints. One tester, a side-combo sleeper who rolls around like “a rotisserie chicken” while she sleeps, called this bed “super comfortable” because of how it supports and cushions at the same time.
Other winning options: Several testers also liked the Brooklyn Aurora Luxe for its heat-stopping abilities, calling it “cool to the touch.”
Product specs
Material: Hybrid (foam and coils) | Firmness: Multiple available: Plush, medium-firm, firm (testers spent most time on the medium firm, a 6 out of 10) | Trial period: 100 nights | Warranty: 10 years | Shipping: Free shipping and returns | Certifications: Greenguard Gold certified and CertiPUR-US certified foam
Best Firm King-Size Mattress: Titan Plus
Pros
- Designed to support larger bodies
- Stays cool
- Has strong edge support
- Available in a variety of king-size options, including split California king
Cons
- No eco-related certifications
- Shorter warranty (10 years vs lifetime)
Why we picked it: The Titan Plus is the firmest on our list and one we’ve recommended for back pain before, with a tester noting zero sinkage and even comparing the top layer’s hardness to a rock. With “fantastic” edge support, according to one tester, you can spread out from end to end on the Titan Plus, allowing you to take full advantage of the larger king size. And people who need a little boost getting up will be able to push off the sides of the bed for support.
Our fave features: The dense gel foam and strong steel coil layers keep things pretty cool. In our testing, the bed’s temperature went up by just under 6 degrees Farenheit after a tester laid in it for five minutes. On our scale, that’s great news. If you know you run hot, you can also add the GlacioTex Cooling cover to your purchase.
Who it's for: The Titan Plus supports up to 1,000 pounds total and is one of the best options for heavier-weight sleepers because it doesn’t allow for enough sinkage to throw your spine out of whack. Dr. Rasouli also recommends firm mattresses like this one for stomach sleepers who need the back support.
Leigh Hanke, MD, MS, BA, assistant professor of Orthopaedics and Rehabilitation at Yale School of Medicine, tells SELF that the firmer a mattress is, the more support it offers your lower back. “So the best advice is to go with the most firm mattress you can tolerate,” she recommends. “People without back pain can get away with softer pillow foam toppers, but this does not provide support, so it can aggravate back pain or prior back injuries."
Product specs
Material: Hybrid (foam and coils) | Firmness: Firm, a 7.5 out of 10 | Trial period: 120 nights | Warranty: 10 years | Shipping: Free shipping (except to AK and HI)
How to find the best king-size mattress for you
You spend about a third of your life sleeping, so it’s important to max out your comfort and ensure you’re getting the highest-quality rest possible. When considering what mattress is right for you, Dr. Petkus says there are a few main factors to consider, no matter what size you’re buying: firmness, support, materials, and durability. But ultimately, how you choose a mattress will come down to preferences.
Materials
The four main types of mattresses—innerspring, foam, latex, and hybrid—have different strengths. While Dr. Hanke says there’s “no one type of mattress that is good for anyone,” from a health POV, she says the goal is to pick an option that supports your spine in the neutral position while you sleep. Here’s what to know about each type.
Innerspring
Innerspring options, which are made with metal coils topped with padding, are “bouncy and supportive,” says Dr. Petkus. Innersprings can keep hot sleepers cooler “since the [coils] tend to have the best airflow,” he adds. If your concern is back pain, innerspring mattresses can offer sturdy support, Dr. Rasouli adds. “However, these may lack pressure relief.”
Memory Foam
Memory foam beds mold to the body and can offer a lot of pressure relief. Experts say that makes them good for people who like the feel of a soft mattress, people with joint or back pain, and side sleepers. They are also generally great at isolating motion because foam tends to absorb impact well.
Latex
Latex mattresses use natural or synthetic latex foam to serve as their support system. Latex tends to be firmer than memory foam, but a tad more giving than innersprings—making it a solid option for back and stomach sleepers. They also tend to provide better pressure relief than traditional foam mattresses and are often highly responsive, making them easy to move around on.
Hybrid
These versatile mattresses are made up of both foam and springs, and therefore blend some qualities from each. “Hybrids use innerspring coils underneath layers of memory foam [or latex], giving you contouring comfort and adequate pressure relief while still providing support,” Dr. Petkus says.
Firmness
Mattress firmnesses describes how a bed feels when you get into it. It’s a subjective metric that often comes on a scale of 1 (softest) to 10 (firmest). While the best firmness for you is a matter of personal preference, research has shown that medium-firm mattresses can help people with back pain get better sleep, and tend to provide adequate support and comfort for most sleepers.
Your sleep position could direct your firmness choice, too. Experts say side sleepers benefit from softer mattresses that’ll help them avoid hip and shoulder pain (spots where weight is concentrated in this position, which can lead to pressure buildup). For back sleepers, medium-firm offers the balance of support and cushion to help the spine achieve its natural curvature. And stomach sleepers fare well with a firm bed’s support in order to keep their hips from sagging and falling out of spinal alignment.
Pressure relief
Pressure relief refers to how well a mattress can distribute weight across the surface of the bed. To Dr. Rasouli, it’s a key consideration for folks with back pain in order to “reduce strain on pressure points, particularly on the lower back.” Dr. Petkus adds that many side sleepers and those with achy joints benefit from a pressure-relieving mattress too. “A mattress with this feature will conform to your body a little, taking the pressure off your hips and shoulders,” he says.
Motion isolation
Motion isolation, or how well your mattress prevents movements from one side of the bed from rippling over to the other, is a top issue for anyone who sleeps with another person or pet—even in a king-size bed. Dr. Petkus advises light sleepers to “look for high marks” on motion transfer, because it affects how much you feel someone else’s tossing and turning or late-night arrivals in bed (and thus, what kind of sleep you get).
Cooling
“It is essential for your body to be able to cool off during the night,” Alex Dimitriu, MD, board-certified psychiatrist and the founder of Menlo Park Psychiatry and Sleep Medicine, previously told SELF. “Research has found that [this] makes us sleep deeper and possibly longer.” That’s why finding a mattress that’s built with breathable, heat-dissipating materials and layers that promote airflow should be a top priority for folks.
Who is a king-size mattress best for?
According to Dr. Petkus, “anyone who values their personal space, even when sleeping next to someone, can benefit.” But there are some people who might be especially suited to a king over a smaller mattress. “Tall people would probably sleep better in a king-size mattress with a partner,” says Dr. Hanke. “The idea is that you don't want to be sleeping in an awkward condensed position.” She adds that if you’re a couple with kids who like to crawl into your bed sometimes, you may want to opt for a king for the most spacious setting for a group snuggle.
The extra surface area can also be helpful for combination sleepers, says Dr. Rasouli: “Those who shift positions during the night can benefit from the added space to find comfortable positions that alleviate pressure on the spine,” he says.
Types of king-size mattresses
There are a few different size variations on a king mattress that are available. You can get a standard king (which is just over a foot wider than a queen), a split king (which essentially sticks two extra-long twin mattresses together for more customization), or a California king (which is slightly narrower but longer than a typical king). What you choose depends on your needs and those of your partner. We broke down the options a bit more below:
