In the United States, there are 6 common mattress sizes—twin, twin XL, full (double), queen, king, and California king. When it comes to determining the best size for you, it is important to consider who you plan to share your bed with, your body type, and the size of your bedroom.

Below we outline the dimensions of each size and explain who they are best suited to.

California King:
72 inches wide by 84 inches long
Recommended room size: 12 feet by 12 feet
Best Suited For: Couples, individuals over 6 feet tall, parent-child co-sleeping

California king beds are 4 inches longer and 4 inches narrower than a standard king. We recommend Cal kings to couples where one or both individuals are over 6 feet tall. The extra length of a Cal king gives taller individuals more legroom, so they don’t have to worry about waking with their feet dangling off the edge.

For families who prefer to co-sleep with their children, a California king provides enough space for both adults and one to two small children.

King:
76 inches wide by 80 inches long
Recommended room size: 12 feet by 12 feet
Best Suited For: Couples, parent-child co-sleeping

Standard king size mattresses are a great option for couples. With 38 inches of personal space, each sleeper has plenty of room to stretch out and find the most comfortable sleep position possible. In most cases, a king size mattress is long enough for sleepers who are 6 feet tall and under. Plus, if your partner tends to toss and turn during sleep, you will be less likely to feel their movements on a large king size bed.

As with a Cal king, a standard king provides enough space for child-parent co-sleeping without causing anyone to feel cramped or uncomfortable.

Many mattress brands also offer split king mattresses, which are two twin XL mattresses placed side by side. This is an ideal choice for couples who have different body types and sleep styles because it allows couples to select a different firmness on each side of the bed.

Queen:
60 inches wide by 80 inches long
Recommended room size: 10 feet by 10 feet
Best Suited For: Couples, solo adult sleepers

Queen mattresses are one of the most common sizes for couples and single adults who prefer more room to stretch out. Queens provide 30 inches of space to each sleeper, which is typically enough for most average side sleepers. However, larger couples, where one or both sleepers are 250 pounds or more, will likely be more comfortable on a king size mattress.

Queen beds fit well in most spaces, while still leaving room for other bedroom furniture. They are also a great choice for a guest bedroom or vacation rental.

Full (Double):
54 inches wide by 75 inches long
Recommended room size: 9 feet by 10 feet
Best Suited For: Solo adult sleepers, growing children and teens, those with limited space

Full size beds, also referred to as “double beds,” are great for growing teens and single adult sleepers. If you live in a small city apartment and are limited on space, a full mattress won’t take up too much room and will still provide you with a comfortable sleep space. Fulls are also a great mattress size for a guest bedroom.

While full mattresses are a versatile option for single sleepers, we don’t recommend this size for more than one sleeper or for individuals 6 feet or taller.

Twin XL:
38 inches wide by 80 inches long
Recommended room size: 8 feet by 10 feet
Best Suited For: Solo adult sleepers over 6 feet tall, growing children and teens, those with limited space

While twin size mattresses are best suited to children, twin XLs work well for single adult sleepers and teenagers who are 6 feet or taller. Twin XLs are 6 inches longer than a standard twin, giving taller sleepers plenty of legroom. Since twin XLs are only 38 inches wide, they don’t take up too much space in the room.

Although a twin XL may work for most adults, plus-size individuals, those 250 pounds or more, will likely find this size too narrow.

Twin:
38 inches wide by 74 inches long
Recommended room size: 7 feet by 10 feet
Best Suited For: Children

Twin size mattresses are a popular option for a child’s bedroom. This size is often used in bunk beds, daybeds, and trundle beds, so children have an extra sleep space for sleepovers and guests. A twin size bed also frees up space in a child’s room for a play area and other furniture.

While this size is ideal for most children, adult sleepers may find it too confining, especially larger individuals.

Mattress firmness can vary from brand to brand. However, most companies use a firmness scale from 1 to 10—with 1 being the softest and 10 being the firmest. Generally, brands don’t make mattresses at a 1 or a 10 since they are either too soft or too firm. Therefore, most mattresses range between a 2 and a 9 on the firmness scale.

Below, we outline the various firmness options available and who they are best suited for.

Soft (2): Soft mattresses compress easily, so lightweight sleepers, who tend to experience minimal sinking, experience maximum contouring, and pressure relief on a softer bed. Our softest mattress is our AS5.

Medium-Soft (3 to 4): Mattresses for side sleepers are often medium-soft. This cushions the curves of the body to prevent pressure points. However, it also has a slight firmness to prevent over-sinking. Our medium-soft mattress is the AS4.

Medium (5): Medium mattresses have a balance of compression and firmness most sleepers find supportive and comfortable. This is often recommended for combination sleepers who change positions throughout the night. A medium is also a great option for couples with different sleep positions and body types. Our best-selling AS3 comes in a medium firmness level.

Medium-Firm (6 to 7): Medium-firm beds are best for back sleepers and those with back pain. The firmness of this comfort level ensures the hips and shoulders stay lifted on the mattress, allowing the spine to rest in a neutral position so the muscles in the back can relax and recover during sleep. Most plus-size sleepers also prefer a medium-firm mattress because it is soft enough to reduce pressure points but firm enough to prevent sinking and spinal misalignment. The AS2 is our medium-firm model.

Firm (8 to 10): When resting on the stomach, the natural curve of the spine becomes exaggerated. This can cause the muscles in the back to remain tight throughout the night, leading to tension and pain in the morning. Therefore, stomach sleepers need a firm mattress to keep the hips lifted and aligned with the shoulders. With the body aligned, the spine will rest in a neutral position, helping to ease some of the pressure on the back muscles when stomach sleeping. Our firmest mattress is the AS1.

Your body type determines how much you will sink into the mattress. Too much sinking could cause the spine to curve unnaturally and lead to pain and muscle tension. However, too little sinking may lead to painful pressure points near the joints.

Below, we outline the best mattress firmness for your body type.

Petite Sleepers (130 pounds or less): Lightweight sleepers will naturally experience minimal sinking when resting on a mattress. To experience maximum contouring and pressure relief, petite sleepers may prefer a soft to medium mattress.

Average Weight Sleepers (between 130 and 250 pounds): Average weight sleepers should select a mattress firmness best suited to their sleep position.

Plus-Size Sleepers (250 pounds or more): Heavier individuals often experience excess sinking which can force the spine to bow and tension to build up in the back muscles. Therefore, the best mattresses for plus-size sleepers are often medium-firm. This comfort level ensures the lumbar spine is cradled and supported and the spine is kept neutral. Plus, the slight softness protects the joints from pressure points.

Mattresses for back pain are often medium-firm. This firmness minimizes sinking, ensures the hips and shoulders remain aligned during sleep. A safe, neutral spine allows the muscles in the back to loosen and relax to encourage healing and a faster recovery time.

When side sleeping, the hips and shoulders bear intense pressure. On a firm mattress, sore spots often develop along the sides of the body due to constant friction throughout the night. Therefore, the best mattresses for side sleepers are soft to medium. Softer mattresses will keep the joints cushioned and protected from pressure points.