A standard king is 76 inches wide by 80 inches long. That equals 6′4″ × 6′8″, or 193 × 203 cm. Its sleeping surface is 6,080 square inches.
People often mix it up with the California king, queen, and split king. This guide sets them straight. It also covers frames, bedding, and room size for a king bed.
King Bed Size and Dimensions
King Bed Size in Inches
A standard king bed size is 76 inches wide and 80 inches long.These king mattress dimensions refer to the mattress, not the larger bed frame.
King Bed Size in Feet
A standard king bed size is 6 ft 4 in wide and 6 ft 8 in long.The king mattress size provides a spacious sleeping surface for two people.
King Bed Size in Cm
A standard king bed size is 193 cm wide and 203 cm long.These king mattress dimensions are based on the standard Eastern king size.
King Mattress Size and Surface Area
Multiply 76 by 80. You get 6,080 square inches, or about 42.2 square feet.A queen offers 4,800 square inches. So a king gives you 1,280 more, or roughly 27% extra space.
Space Per Sleeper on a King Bed
Two adults get 38 inches each on a king. That is the width of a Twin XL.
| Bed Size | Width Per Adult |
|---|---|
| Full | 26.5 in |
| Queen | 30 in |
| King | 38 in |
Add a child or pet and three sleepers still get about 25 inches each.
King Bed Size vs. Queen and California King
King vs. Queen Size Bed
Both beds are 80 inches long. The king is 16 inches wider. That is about 27% more width.
Sheets do not swap between the two. A queen fitted sheet is too narrow for a king.
King vs. California King
A California king is 4 inches narrower and 4 inches longer. Its surface area is 6,048 square inches, just 32 less than a king.
Tall sleepers often prefer it, especially back and stomach sleepers. Brands set the “tall” cutoff anywhere from 6 feet to 6′4″. Cal king sheets and frames also cost more and are harder to find.
Split King vs. Standard King
A split king is two Twin XL mattresses (38 × 80 inches each). Together they match the king’s 76 × 80 footprint.
Each side can have its own firmness and adjustable base. The trade-off is a small gap in the middle. You also need two Twin XL fitted sheets. A split California king uses two 36 × 84 inch mattresses.
More Posts:Double Bed Size
Types of King Size Beds
Short King and Super King
A short king is 72 inches wide and 75 inches long. RVs and campers often use it.
A super king is 72 × 78 inches. Both are as wide as a Cal king but shorter than a standard king. Expect custom orders for mattresses and bedding.
Wyoming, Texas, Alberta, and Alaskan King
| Type | Width | Length |
|---|---|---|
| Wyoming King | 84 in | 84 in |
| Texas King | 80 in | 98 in |
| Alberta King | 96 in | 96 in |
| Alaskan King | 108 in | 108 in |
The Texas king is the longest rectangle, so it suits very tall sleepers. The Alaskan king is 9 × 9 feet, and mattress makers suggest a room of about 16 × 16 feet for it.
King Size Bed in the UK, Europe, and Australia
A “king” is not the same everywhere. A UK king is about 59 to 60 × 78 inches (150 × 200 cm). That is much narrower than a US king.
A European king is often 160 × 200 cm (about 63 × 79 inches). An Australian king is 72 × 80 inches.
Room Size for a King Bed
Minimum Room Size for a King Bed
Retailers list anywhere from 10 × 12 to 13 × 13 feet. A 12 × 12 foot room is the safest target.
A 10 × 12 foot room can work with very little furniture. For reference, mattress makers often cite 14 × 16 feet as the average US bedroom.
Clearance and Layout Math
The Sleep Foundation suggests about 24 inches of space on each side of the bed. Up to 36 inches feels roomier.
A 12-foot-wide room is 144 inches. Subtract 76, then split the rest. That leaves 34 inches per side. A 10-foot-wide room leaves only 22 inches per side, which is tight.
Dressers need about 36 inches in front to open drawers.
King Bed Size FAQs
How big is a king size bed?
A king is 76 × 80 inches (6′4″ × 6′8″, or 193 × 203 cm). It gives two adults 38 inches each.
Is a king bed bigger than a queen?
Yes. It is the same length but 16 inches wider. That adds 1,280 square inches of sleeping space.
Is a king bed bigger than a California king?
Slightly, by surface area (6,080 vs. 6,048 square inches). A Cal king is 4 inches longer but 4 inches narrower.
What size room do I need for a king bed?
Aim for about 12 × 12 feet. A 10 × 12 foot room can fit one, but space gets tight.
What size sheets fit a king bed?
Use king sheets, with a 76 × 80 inch fitted sheet. Choose deep-pocket sheets for thick mattresses. Cal king sheets will not fit.
Do two Twin XL mattresses make a king?
Yes. Two 38 × 80 inch Twin XLs add up to 76 × 80 inches. This setup is called a split king.