Mattress Buying Guide

One brand's "medium" might be another brand's "firm." To help you compare, we measure each mattress against an industry standard using a scale from 1 (extremely soft) to 10 (extremely firm). Check our ratings for more, and see best firm mattresses and the best soft mattresses from our tests.

To test for durability, we run a 300-plus-pound wood roller across the surface of each mattress 30,000 times—simulating eight to 10 years of use. Our tests found that some of the most wallet-friendly mattresses can also be quite durable. See our ratings chart for more.

Some mattresses allow more airflow than others. That means less trapped heat. Generally, innerspring models retain less heat than foam because of the coils, but how hot you sleep ultimately depends on a mattress's overall construction. See “Best Mattresses for Hot Sleepers” for more.

Stability refers to a mattress's ability to isolate motion—allowing a sleep partner (or pet or child) on one side of the mattress to shift without jostling a sleeper on the other side. Generally, foam models have better stability than innerspring. (Note: Innersprings with individually wrapped coils do better than those without.) To see details in our ratings, click "Best For" and filter for high-performing mattresses that also offer good stabilization. You can also read “Best Mattresses for Couples.”

That "new mattress smell" is what you detect when volatile organic compounds (VOCs) escape into the air from the foam, upholstery, and adhesive in a mattress. In high concentrations released indoors, these chemicals can lead to negative health effects. So before using a mattress, let it off-gas with the windows open until the odor dissipates. If you’re sensitive to chemicals, have allergies, or have a respiratory condition, consider a mattress that is certified for low levels of potentially toxic chemicals. See the best low-VOC mattresses and certifications for more.

A good mattress will keep your spine aligned throughout the night, so you don't wake up feeling achy. That alignment, or support, depends on not just the mattress itself but also how it interacts with the weight of your body, how that weight is distributed, and your sleep position. We assess each mattress for its ability to support side and back sleepers as well as large and small sleepers. Explore our ratings for more, and check our reviews of the best mattresses for side sleepers and for back sleepers.

Truth: The best mattress thickness is a matter of personal preference. A thick mattress might appear luxurious, but it's really about what's adding the height. Poor-quality fillers can be prone to sagging and softening. In our ratings the average foam mattress is about 11 inches, the average innerspring is about 13 inches, and the average adjustable air mattress is 12½ inches.

Truth: They vary wildly. Part innerspring and part foam, these mattresses offer the resilience of coils with the cuddle of foam. When you shop, note the number and height of the coils and thickness of the foam layers. Mattresses with a higher proportion of foam will feel more foam-forward, and those with less will feel more like an innerspring.

Truth: The right choice is not about the mattress itself, but how supported you feel on it. Your spine should feel aligned, not flexed or twisted—whether the mattress is firm, soft, or something in between. In fact, a Utica College study found that the best mattress for back pain is one that’s medium-firm—however the user describes it.

Truth: They don’t necessarily retain less heat than nongel foams. That’s because while gel-infused foams might feel cool to the touch at first, they’ll eventually warm up with extended exposure to body heat. And while some foams are more breathable than others, none can actively cool you, unless equipped with a system of fans or chilled water (features more likely found in cooling mattress pads).

Truth: Not necessarily. Plenty of our high-performing mattresses are in the $1,000 range, and there are even some for under $600. Mattresses that cost around $2,000 or more tend to have extras that are nice to have (such as an organic-cotton cover and latex foams) but aren’t necessarily crucial to back support or durability.

Truth: A mattress topper is unable to firm up a mattress that feels too soft, much less add support to an old mattress that’s lumpy or sagging. Mattress toppers are best used to dial up the plushness of a mattress that feels too firm.