King vs. Full: What’s the Difference?

Looking for a new mattress can be a tricky business—considering room size, measuring the bed frame, and deciding if the mattress is for a master bedroom or guest room. Larger mattresses like king size beds will need extra space, while full mattresses fit perfectly in smaller rooms.

In our article, we go over the differences between a king and full size mattress and outline other standard mattress sizes.

What’s a King Size Mattress?

A king, or eastern king, size mattress measures 76 inches by 80 inches—the largest standard size available. A king bed is equivalent to two twin XL beds placed side by side—a perfect mattress size for couples who want more personal space.

King mattresses are also available as a split king option. Couples can enjoy customized comfort and support for better sleep.

Pricing

The price for a king size mattress ranges between $700 to $4000, depending on the sleep technologies and materials included in the bed.

Recommended Room Space

Because king mattresses are so large, master bedrooms at least 12 feet by 12 feet are best, providing enough space for furniture and walking area.

Pros

• Perfect for couples
• Ideal for master bedrooms
• Split king option

Cons

• Too large for some bedrooms
• Expensive
• Difficult to move

We love the king size Amerisleep AS3 because it’s great for couples. King beds are often unnecessary for single sleepers, which is why we love the AS3 for couples. With its medium feel, the Amerisleep AS3 provides a balance of cushioning and support for all types of sleepers and isolates motion well.

The Amerisleep AS3 is made in the USA and CertiPUR-US® certified. It won’t off-gas—that factory-like smell some new mattresses have.  

Amerisleep mattresses include free shipping and returns, a 100-night sleep trial, and a 20-year limited warranty. 

How Lying Down Feels

The AS3 provides just enough cushioning to protect your hips and shoulders, but won’t cause you to sink or feel stuck in bed. As an all-foam mattress, the AS3 isolates motion well. This way, people who share a bed won’t disrupt each other when switching positioning or getting up for a late-night glass of water.

The ergonomic support zones in the AS3 lift your body and prevent achy pressure build-up. With firmer support, the AS3 aligns your spine to reduce back pain and help you sleep peacefully.

Inside the Mattress

The AS3 is made from three layers of foam. Over the foam layers is a breathable cover built to dissipate heat and moisture. 

At the top of the AS3 is Bio-Pur®, Amerisleep’s proprietary memory foam found in most of their mattresses. Bio-Pur® is plant-based and mainly made out of castor oil rather than petroleum-based oils. This way, the Bio-Pur® doesn’t trap heat, cause motion transfer, or sag easily.

Next is a layer of Affinity foam. It contains a zoned technology called HIVE® that’s built to evenly distribute your body weight and prevent pressure point build-up. The technology is the softest around your hips and shoulders, then firm under your head, back, and legs.

The bottom of the AS3 is made from Bio-Core®, a sturdy base designed to support your spine. It also plays a critical role in helping your mattress last, being resistant to sags, soft spots, and lumps. 

What’s a Full Size Mattress?

A full size mattress is 56 inches by 75 inches. Also known as a “double bed,” full mattresses are an excellent choice for single sleepers—teenagers, college students, and adults with limited living space, like studio apartments.

Full size beds have more width than a twin, providing extra space to stretch. Double mattresses are commonly found in college dorm rooms and are also good for mattresses for guest bedrooms.

Pricing

A full size or double bed costs between $500 to $3000. The price depends on special features and the number of materials inside the mattress.

Recommended Room Space

Full beds are perfect for smaller bedrooms, measuring 10 feet by 12 feet, leaving plenty of room for additional furniture and walking space.

Pros

• Excellent for single sleepers
• Fits small bedrooms
• Budget-friendly
• Easier to move

Cons

• Not enough room for couples
• Too short for taller sleepers

The Vaya Mattress is a highly popular mattress when you’re trying to save money. Still, you don’t have to sacrifice your comfort just because you want to save money. The Vaya Mattress is an all-foam mattress with lots of bounce, support, and pressure relief. Its medium firmness works well for all types of sleepers, too!

Vaya mattresses are made in the USA and CertiPUR-US® certified. You receive free shipping, free returns, a 100-night risk-free trial, and a 10-year warranty with purchase.

How Lying Down Feels

The Vaya Mattress provides ample spinal support without feeling firm or uncomfortable. It contours to your curves to soothe joint and muscle pain, but doesn’t sag or cause you to sink. The cooling foams and knit cover dissipate body heat and moisture, so hot sleepers can relax and sleep undisturbed.

Inside the Mattress

Vaya manages to keep their prices affordable by streamlining the Vaya Mattress’s design. Despite being 12 inches thick, the Vaya Mattress only has two layers. 

The first layer in the mattress is 3 inches of Vaya Comfort Foam. It performs similarly to latex, being springy, supportive, and breathable. 

The second layer is 9 inches of Vaya Base Foam. This thick layer has multiple functions, including aligning your spine, lifting your body, and being durable against wear. Vaya Base Foam ensures your mattress lasts for years without becoming saggy or unsupportive.

Other Mattress Sizes

If the mattress dimensions of a king or a full aren’t right for the space you have in mind, a twin, twin XL, queen, and California king, might be the best mattress for you.

Twin Mattress

Twin size mattresses are 38 inches by 75 inches—the smallest mattress size available. Twin beds are perfect for children and compatible with bunk beds, so families with more than one child can utilize space.

Twin XL Mattress

Twin XL size mattresses measure 38 inches by 80 inches; 5 inches longer than a twin bed. Twin XL mattresses are great for individuals taller than 6 feet and fit nicely in smaller spaces.

Queen Mattress

Queen size mattresses are 60 inches by 80 inches. Queen beds are a popular mattress size with single adults living on their own, offering plenty of room to sprawl out. They’re also a good option for couples who like to cuddle.

California King Mattress

California king size mattresses measure 72 inches by 84 inches, the same area as a standard king size, except longer and narrower. California king beds are excellent for taller couples who need more legroom.

Though not as widely accessible as a split king, split California king options are also available for couples looking for personalized comfort and support.

Other Things to Consider

How much bigger is a king than a full?

A king size mattress is 20 inches wider and 5 inches longer, an excellent option for couples. King size beds provide 38 inches of personal space and extra length for taller sleepers. Full size mattresses are better for single sleepers.

Is a full bed big enough for two?

Full beds are only 56 inches wide—that’s 28 inches of wiggle room per person, a whole 10 inches less than what a king mattress offers (38 inches). Full mattresses may be too small for couples, but they’re great for single adults.

What size bed do most couples have?

Most couples sleep comfortably on a queen, king, or California king size mattress, depending on budget and available space. Other mattress sizes, including twin, twin XL, and full, will feel too small and cramped for two people.

Is there a bigger size than king?

Yes, there are oversized mattresses that you can custom order. Such variations include:

• Wyoming king: 84 inches by 84 inches
• Texas king: 80 inches by 98 inches
• Alaska king: 108 inches by 108 inches

Do two twins equal a king?

No, two standard twin beds do not equal a king or any other mattress size. Their length is 5 inches shorter than a standard king. It is two twin XL mattresses that, when pushed together, take up the same amount of space as a king mattress.

Conclusion

Whether you choose a king or full size bed, the best mattress will accommodate your living space and add to a comfortable atmosphere for better sleep.