The A-to-Z Mattress Sizes & Bed Dimensions Guide

• Dimensions: 27.5 inches wide by 52 inches long (70cm x 132cm)
• Recommended For: Babies.
• Not Recommended For: Anyone larger than a toddler.
• Minimum Room Size: 87” x 82”

The Crib mattress is the smallest standard sized bed and designed for exclusive use by babies who sleep in an enclosed crib.

Crib mattresses are firmer than a standard adult mattress as softer beds can be potentially dangerous for a baby’s breathing since they can cause suffocation, and a firmer mattress provides more support for growing bones.

Crib mattresses are designed to fit a standard crib, around 28 x 52 inches. There should be no more than a 1½ inch (4cm) gap between the side or end of the crib when the mattress is pushed all the way into a corner.

This translates to roughly two fingers. Any gap larger than this means the fit is incorrect; bigger gaps are a potential suffocation hazard.

Crib mattresses are often made from light materials that allow for portability and ease of cleaning.

• Dimensions: 27.5 inches wide by 52 inches long (70cm x 132cm)
• Recommended For: Toddlers who have outgrown the crib and are graduating to their first bed.
• Not Recommended For: Babies. Toddler mattresses are generally softer than crib mattresses and present a suffocation hazard for infants.
• Minimum Room Size: 87” x 82”

As the name suggests, Toddler mattresses are designed to be a first bed once a child has outgrown the crib. They are the exact same size as a Crib mattress and act as an intermediary between the crib and a Junior or Single bed.

The differences between a Crib mattress and a Toddler mattress lie more in how they’re used more than anything else.

Obviously, a toddler bed is not enclosed like a crib (although they may have side rails), and a toddler bed can make use of pillows, a comforter, and a top sheet, none of which are used in a crib.

Generally, Toddler mattresses will be softer than Crib mattresses as there is not the same suffocation danger. At this stage, beds can begin to be tailored more toward comfort than practicality.

Because Crib and Toddler mattresses are the same size, double-sided mattresses that cater to infants and toddlers are often a popular choice for parents who don’t want to buy two beds that will soon be grown out of.

• Dimensions: 27.5 inches wide by 63 inches long. (70 x 160cm)
• Recommended For: Younger children.
• Not Recommended For: Older children/teenagers.
• Minimum Room Size: 99” x 105”

The Junior mattress is the same width and 11 inches (28cm) longer than Crib and Toddler mattresses.

The Junior mattress is not as widely popular as other standard sizes. Youth beds, like crib beds, generally have a shorter useful life due to being outgrown.

Still, the Junior acts as a good intermediary for children who may have outgrown a Toddler bed but don’t yet require the extra room that comes with an adult-sized bed.

They also act as a more economical option for parents who don’t wish to invest in a Toddler bed — the Junior is suitable for toddlers and should last them through most of their childhood.

• Dimensions: 38.5 inches wide by 74.5 inches long. (98 x 189cm)
• Recommended For: Children, small to average single adults. Rooms with not a lot of space.
• Not Recommended For: Larger adults, people who like to spread out or toss and turn, couples.
• Minimum Room Size: 99” x 105”

The standard Twin (Single) mattress is 11 inches (28cm) wider and 11.5 inches (29cm) longer than a Junior mattress.

The Twin mattress is the minimum size that would be suitable for most adults, providing the minimum amount of room for an adult to sleep comfortably. They are also a good option as a kids’ bed that would be suitable enough to last well into their teens.

Twin beds are perfect for small rooms where space is at a premium or where two or more beds are required, such as a guest bedroom or holiday home.

A twin is probably not well suited to larger adults, those who like to spread and stretch out in bed, or who toss and turn a lot.

• Dimensions: 38.5 inches wide by 79.5 long (98 x 202cm).
• Recommended For: Children, tall single adults. Rooms with not a lot of space.
• Not Recommended For: Larger adults, couples.
• Minimum Room Size: 104” x 105”

The standard Twin XL mattress is 5 inches (13cm) longer than a standard Twin/Single bed.

Like the Twin, the Twin XL is suitable for a single adult, albeit ones who need a bit more length, so if you’re on the tall side, a Twin XL should suit you better than a standard Twin while still being able to fit into pretty much the same sized space.

• Dimensions: 53.5 inches wide by 74.5 inches long (136 x 189cm).
• Recommended For: Single adults, small to average couples, couples who enjoy sleeping close.
• Not Recommended For: Larger couples.
• Minimum Room Size: 114” x 105”

The standard Full (Double) mattress is 15 inches (38cm) wider and 5 inches (13cm) shorter than a standard Twin XL.

A Full-size bed is perfect for a single adult who prefers a bit more room to spread out but doesn’t need the extra size of a Queen.

It is also the minimum size that would be suitable for a couple, though most couples would probably prefer a Queen unless they prefer close-quarters sleeping, are restricted by space, or both are on the smaller than average side.

• Dimensions: 60 inches wide by 79.5 inches long (152 x 202cm).
• Recommended For: Most couples (most popular bed size).
• Not Recommended For: Couples with children or multiple pets who share the bed.
• Minimum Room Size: 120” x 110”

The standard Queen mattress measures 6.5 inches (16.5cm) wider and 5 inches (13cm) longer than a Full/Double mattress.

The Queen bed is pretty much the gold standard for adult couples, being big enough that most couples have enough space to sleep comfortably without being too large to fit into most spaces.

Its suitability for most average couples means it is the size of choice for between a third to a half of all American adults.

• Dimensions: 76 inches wide and 79.5 inches long (193 x 202cm).
• Recommended For: Couples who enjoy their own sleeping space, easily disturbed partners, couples with children and pets who share the bed
• Not Recommended For: Rooms with not a lot of space.
• Minimum Room Size: 136” x 110”

The standard King mattress measures 16 inches (41cm) wider and the same length as a standard Queen bed.

The King size bed is where you really start seeing some personal space. For couples who consider themselves sleep connoisseurs and really appreciate having extra room to spread out without touching their partner, the King mattress will fit the bill for most.

A King size is a sensible option for couples with a child or two who like to share the bed, or perhaps a pet that likes to curl up and sleep with them, providing there is adequate space for this large bed.

• Dimensions: 73 inches wide and 83.5 inches long (183 x 212cm)
• Recommended For: Tall couples, couples who enjoy their own sleeping space, easily disturbed partners, couples with children and pets who share the bed
• Not Recommended For: Rooms with not a lot of space.
• Minimum Room Size: 132” x 114”

The standard California King mattress measures 3 inches (7.5cm) narrower and 4 inches (10cm) longer than a standard King bed.

It is the largest ‘standard’ sized mattress that is commonly available. While bigger sizes are available, most people would not go larger than this.

The California King is one bed with a real aura of luxury — and acts almost as a status symbol, given their origin in the 1960s when a Los Angles company began making oversize beds for celebrity mansions.

You don’t need to have a mansion to own one — but you do need a bit more space to work with than your average bed.

Even couples on the larger side of average will have room to spare on a California King. If you have space for one, the California King is the perfect option for couples who are easily disturbed by their sleeping partner, who like to really spread out, or who toss and turn a lot.

It’s the perfect family option, too — if you have multiple kids who like to share the bed, multiple pets, or perhaps just one large one, there should be plenty of room for all on the California King.

For couples who need a bit of extra width but either don’t quite need the size of a King or are restricted by available space, the Olympic Queen bed, measuring 66 inches wide by 80 inches (168 x 203cm), gives an extra six inches of width for couples who like a little extra distance between them.

If you thought the California King is as big as it gets, think again. Measuring in at 84 x 84 inches (213 x 213cm), the Wyoming King is an excellent choice for couples with more than one child, multiple or large pets who like to share the bed — providing the bedroom is big enough to fit a bed this large!

Unless you’re going for a crazy custom bed, this is as likely as big as you’ll find. The King of the Kings, the Alaskan King, requires a lot of space, measuring in at 108 x 108 inches (274 x 274cm).

Some families with young children enjoy all sleeping together in one bed, and this is one size of mattress that caters well to family bonding — or couples with a couple of spoiled Saint Bernards!