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A good mattress can help you get a better night’s sleep and reduce aches and pains. If you’re consistently waking up with soreness, it may be time for a new mattress — and choosing the right mattress for your needs can help you get the best night’s sleep. The goal, says Josh Tal, PhD, of Joshua Tal, PhD and Associates Sleep and Health Psychotherapists, is to minimize discomfort to keep you asleep.

if you can’t remember when you last got a new bed — it’s probably time to look for a new one. “On average, the lifespan of a mattress is approximately around 10 years,” says Vaishnavi Kundel, MD, an assistant professor of medicine at the Icahn School of Medicine at Mount Sinai. ”If you notice sagging, this could lead to uneven spinal support which may contribute to aches and pains, in addition to poor sleep, and it may be time to change your mattress.”

Since it might be time for you to go mattress shopping, we talked to the experts to get some advice on what to look for. Here’s what to consider when shopping for a mattress, whether you’re already set on finding the best mattress-in-a-box in or still deciding whether to buy online or in person.

Side sleepers should choose a mattress which relieves pressure points at the shoulders and hips. Soft to medium-firm mattresses help alleviate pressure because they allow the shoulders and hips to sink into the bed and properly align the spine and prevent sore in the hips and shoulders — meaning a more comfortable night’s sleep, without having to turn from side to side in a struggle for comfort.

Back sleepers will benefit from medium to firm mattresses to provide enough support to keep the spine straight and aligned. Back sleepers should stay away from soft mattresses, since a bed that’s soft enough to sink into won’t have sufficient support, and can lead to misalignment of the spine and potentially exacerbate back issues.

Like back sleepers, stomach sleepers usually fare better on a firmer mattress that can properly support the spine and keep it in a straight line. A mattress that’s too soft may cause the spine to sink into the bed leading to misalignment.

Those who switch between sleeping on their back, side or stomach, will need a mattress that accommodates their changing sleep positions. If you move around as you sleep, but predominantly sleep in two positions, it’s best to choose a mattress somewhere between the recommended firmness levels. Some hybrid mattresses we’ve tried, like the Leesa Legend Hybrid, are soft but still supportive so they can serve both back and side sleepers.

How to choose the best mattress for your body type

Many of our experts advised that body weight is an important consideration when choosing a mattress — you’ll still want to keep your sleep position in mind, but depending on your size you might want to adjust your thinking about how firm a mattress you need.

David Rubin, director of product testing at The Sleep Doctor, suggests that people who weigh over 230 pounds choose a firmer mattress, while lightweight sleepers will fare better with a softer mattress. Rubin adds that people who weigh over 230 pounds choose a mattress that offers a durable surface — such as a hybrid or innerspring mattress — which helps prevent excessive sagging.

Nicholas R. Beatty, DO, assistant attending physiatrist at the Hospital for Special Surgery, agrees, “ Lighter or petite individuals may do well with a foam mattress with medium-firm or slightly less support. Heavier or larger frame individuals, to achieve that same alignment, may need to opt for something more firm, but then may add a pillow-top softer material to avoid increased body-contact forces.”

There are also mattresses that are specifically designed to support heavier individuals, such as a Big Fig mattress, which may be beneficial for heavier individuals who’ve had a hard time finding the proper support.

Choosing a mattress for back pain is complicated because it can have many causes making it difficult to pinpoint it solely to the mattress. When we asked Dr. Beatty the type of mattress back pain sufferers should choose, he said “It depends. The short answer is medium-firm.”

Beatty. also goes on to say, “With sleeping, some types of back pain (e.g. spine arthritis) respond well to side sleeping whereas other individuals might have worsened pain in side sleeping (e.g. certain types of disc herniations).

“A good rule of thumb would be to avoid stomach/prone sleeping or place a pillow under your pelvis/hips to reduce the extension of your low back, and aim for another position of comfort with a medium-firm mattress with good spine alignment, including not using too many pillows to misalign the neck from the rest of your body.”

Do you sleep hot? Or cold? Dr. Beatty advises individuals to “consider temperature regulation, room temperature, and climate in your decision-making, which can impact sleep.”

If you’re a hot sleeper you’ll want to avoid memory foam mattresses; since the foam will mold to your body they’ll likely keep you hot. There are some newer foam mattresses designed to beat the heat with features like perforated layers, or  built-in or so-called “phase change” materials that wick away heat.

In our mattress tests, we also found that perforated foam layers help with air circulation and releasing heat. Some mattresses may also have a top fabric that helps wick away moisture or feel cool to the touch. You can also opt for an innerspring mattress or a firmer mattress where your body won’t sink into the bed as much which allows for air circulation around the body which helps keep you cool.

Understanding different types of mattress

Foam mattresses are popular for their ability to cradle the body and relieve pressure points while still providing support. They are primarily made with memory foam, polyurethane foam or a combination of both. Memory foam molds to the shape of your body and polyurethane foam compresses like memory foam but does not mold to the shape of your body. Foam mattresses are good for reducing contact pressure points such as the hips and shoulders, making them a good choice for side sleepers.

Foam is also excellent for motion isolation, minimizing movement from transferring to the other side of the bed — so it’s a good material for couples with different sleep positions or comfort needs. The downside to foam mattresses is that some people find them hot, however, many brands now offer cooling styles to help combat overheating.

Innerspring mattresses are mattresses with coils inside the base of the mattress. The coils may be continuous which means they are connected to each other or pocketed which means each coil is individually wrapped. Pocketed coils help prevent motion transfer but can also make the mattress pricier. Coils offer different levels of support depending on the thickness, number of coils and type of coil.

Innerspring mattresses can provide firmer support than foam mattresses, making them good for those that need more support. Because you don’t sink into an innerspring mattress as much as with a memory foam, it also feels more like laying on top of the mattress rather than sinking in and hugging your body, which some may prefer.

Some mattresses are made from latex, which can be natural or synthetic. Natural latex comes from the sap of the rubber tree and synthetic latex is designed to mimic the properties of natural latex. Both of these types of latex conform to the body, though not as much as memory foam, and have a buoyant, bouncy feel.

Hybrid mattresses can be any combination of innerspring, memory foam, latex or other materials. Most commonly, they’ll have a base of innersprings with foam and other materials to provide a balance of support and softness. These mattresses suit a broad range of sleepers, and if you’re looking for something that will relieve pressure without giving up some degree of support, a hybrid mattress might be right for you.

An adjustable mattress may be made of any of the materials previously mentioned but can be customized using mechanical tensioning to provide fine-tuned levels of comfort and support. Typically these beds are operated with a remote or smartphone app.These mattresses can lay flat or move to different angles to elevate the feet or head. This allows you to find a comfortable position for activities like reading or watching TV.

Adjustable mattresses are often recommended by sleep experts for health conditions such as acid reflux, snoring, or sleep apnea, as they can be adjusted to help alleviate symptoms.

It’s important to consider how hard or soft a bed you want (or need). When shopping for a mattress, you’ll likely see descriptions such as firm, medium firm, plush or soft. There may also be a firmness scale from one to ten, with one being the softest and ten the firmest. Most brands generally carry a range of mattresses from soft to firm. The descriptions give a general idea of how the mattress will feel, however, the firmness rating between brands can be subjective, what may be medium-firm for one brand may be soft for another.

If you’re unsure what will suit you in the long run, multiple experts suggested a medium firm bed for most individuals. You’ll want to make sure you’re in proper alignment which is not always obvious and hard to tell when you’re lying on a bed.

David Rubin, director of product testing at The Sleep Doctor, suggests a simple test, especially for side sleepers, which is to put a line of masking tape down your shirt along the spine while standing straight. Lay on the bed and have someone look to see if the tape is in a straight line, if it’s dipping the mattress isn’t supportive enough. Keep in mind though, the overall goal for choosing a mattress is to minimize discomfort to keep you asleep according to the experts we interviewed.

Mattresses can cost anywhere from a few hundred dollars to several thousand depending on a variety of factors. Larger sizes like king will cost more than the smaller sizes such as full or twin. The more features a mattress comes with such as zoned support, cooling technology, additional layers within the bed and more will raise the price.

Price does not necessarily equate to a better mattress, in most cases it boils down to individual needs. For example, if you’re not a hot sleeper, you can skip buying a mattress with cooling technology and potentially save some money or splurge on other features.

Consider trial periods and return policy

It’s important to look at the mattress trial period and return policy since mattress comfort is very subjective. It’s especially important if you’re shopping online where you can’t lay on the bed before purchasing. Most online brands allow for returns if you’re not satisfied with the bed. You’ll want to read the fine print for the conditions of return as well as any fees such as a return fee or having to ship the mattress back at your expense.

Make sure the trial allows for enough time for your body to adjust to the bed: most brands recommend sleeping on a bed for at least 30 days (some even require that you try a mattress for that period before beginning a return process) and offer a longer trial period.

Understand your delivery options

Most retail stores will offer delivery and set it up in your home for mattress purchases. For mattress-in-a-box options, the box is delivered to your doorstep but some offer delivery and set up as well, but an extra fee may apply. Delivery and set up is a good option for those that don’t want to deal or can’t move the mattress into their home and get it on their existing frame. The downside is it may be inconvenient to schedule a block of time and wait for it. It also often costs extra so you’ll want to factor that in as well.

Getting the mattress delivered to your doorstep allows you to set up the mattress at your convenience. However, these mattresses in a box can weigh over 100 pounds, so it may require multiple people to set up the bed and you’ll also be responsible for getting rid of your old mattress.

The size of the mattress — it shouldn’t be too obvious to point out — should suit your space and your needs. You’ll want to consider how many people (or pets) are sleeping on the bed and the available space you have to place the bed.