King Size Bed Dimensions in Feet: Every King, One Simple Chart

A standard king size bed measures 6 ft 4 in wide by 6 ft 8 in long (76 by 80 inches, or 6.33 by 6.67 ft). A California king swaps width for length at exactly 6 ft by 7 ft, and a split king is two halves of 3 ft 2 in by 6 ft 8 in pushed together. The chart below gives every king variant in feet first, with inches, centimeters, and floor area beside it, because most size guides bury the feet conversion in a footnote or skip it entirely.

Every king size in feet: the full chart

These are mattress dimensions. Frames run bigger, and that difference gets its own section below.

King size	Inches (W x L)	Feet and inches	Decimal feet	Centimeters	Floor area
Standard king (Eastern king)	76 x 80 in	6 ft 4 in x 6 ft 8 in	6.33 x 6.67 ft	193 x 203 cm	42.2 sq ft
California king (Western king)	72 x 84 in	6 ft 0 in x 7 ft 0 in	6.00 x 7.00 ft	183 x 213 cm	42.0 sq ft
Split king (two halves together)	76 x 80 in	6 ft 4 in x 6 ft 8 in	6.33 x 6.67 ft	193 x 203 cm	42.2 sq ft
Wyoming king	84 x 84 in	7 ft 0 in x 7 ft 0 in	7.00 x 7.00 ft	213 x 213 cm	49.0 sq ft
Texas king	80 x 98 in	6 ft 8 in x 8 ft 2 in	6.67 x 8.17 ft	203 x 249 cm	54.4 sq ft
Alberta king	96 x 96 in	8 ft 0 in x 8 ft 0 in	8.00 x 8.00 ft	244 x 244 cm	64.0 sq ft
Alaskan king	108 x 108 in	9 ft 0 in x 9 ft 0 in	9.00 x 9.00 ft	274 x 274 cm	81.0 sq ft

The standard king and California king are the two sizes sold everywhere; their dimensions are the US retail standard confirmed by manufacturer size guides and independent mattress references. The bottom four are oversized specialty sizes, made to order by a small number of makers. Two manufacturers and two independent guides list all four at the same nominal dimensions, but because they are built to order, confirm the exact measurements with the maker before you order a frame or bedding.

How the feet numbers are worked out

Every figure in the chart comes from two conversions. Nothing is rounded until the last step.

1. Divide the inches by 12 to get decimal feet. Standard king width: 76 divided by 12 = 6.33 ft.
2. For feet and inches, keep the whole number as feet and multiply the remainder by 12. The 0.33 left over from the king width: 0.33 x 12 = 4 in, so 6 ft 4 in.
3. For floor area, multiply width by length in inches, then divide by 144 (the square inches in a square foot). Standard king: 76 x 80 = 6,080 sq in, and 6,080 divided by 144 = 42.2 sq ft.

Run the same math on the California king length and it lands on the cleanest number in the chart: 84 divided by 12 = exactly 7 ft, no remainder.

King vs California king in feet

The two standard kings trade the same 4 inches back and forth:

• Width: the standard king wins, 6 ft 4 in against 6 ft 0 in.
• Length: the California king wins, 7 ft 0 in against 6 ft 8 in.
• Floor area: nearly a tie. The standard king covers 42.2 sq ft, the California king 42.0 sq ft, a difference of just 32 square inches. The wider bed is, by a whisker, the bigger bed.
• Space per sleeper: the standard king gives each person 38 in (3 ft 2 in) of width. The California king gives 36 in (3 ft 0 in) each, but adds 4 in of legroom.

So the choice is not bigger against smaller. It is width against length: pick the standard king for elbow room, the California king if anyone sleeping in it is over about 6 ft 2 in, or if the room is long and narrow rather than wide. Whichever king you choose, the rug math is the same – see what size rug for a king bed.

The diagram below draws both footprints to scale, top edges aligned, so the 4-inch trade is visible instead of buried in a table.

Split king dimensions in feet

A split king is not a different size. It is a standard king footprint, 6 ft 4 in by 6 ft 8 in, built from two separate mattresses. Each half is a twin XL: 38 by 80 in, which converts to 3 ft 2 in wide by 6 ft 8 in long, covering 21.1 sq ft. Two halves side by side total exactly 76 by 80 in, the standard king footprint to the inch.

Couples choose it for adjustable bases, where each side tilts independently, or to run two different firmness levels in one bed. It also solves a delivery problem the one-piece kings cannot: a 3 ft 2 in half turns corners and climbs stairs that a 6 ft 4 in single mattress will not.

Oversized king sizes in feet

Past the two retail standards, king sizes turn into specialty territory:

• Wyoming king, 7 ft by 7 ft (49.0 sq ft). The smallest oversized king and the first square one: 8 in wider and 4 in longer than a standard king.
• Texas king, 6 ft 8 in by 8 ft 2 in (54.4 sq ft). Only 4 in wider than a standard king, but 18 in longer, built for very tall sleepers.
• Alberta king, 8 ft by 8 ft (64.0 sq ft). A full foot wider and longer than the Wyoming.
• Alaskan king, 9 ft by 9 ft (81.0 sq ft). The largest king made, close to double the floor area of a standard king (81.0 against 42.2 sq ft), sized for whole-family co-sleeping.

None of these sit in a normal furniture store. They come from specialty makers, the frames and bedding are made to order alongside the mattress, and at 8 ft 2 in to 9 ft of length they need genuinely large bedrooms. Treat the chart dimensions as the nominal standard and get the maker’s spec sheet before committing.

The frame is bigger than the mattress

Everything above is the mattress. The furniture you actually have to fit into the room is the frame, and bed frames typically add 2 to 5 inches per side once rails, headboard, and footboard are counted. The king guides across this site use one declared frame size so the numbers stay comparable: 82 by 86 in for a standard king mattress, which converts to 6 ft 10 in wide by 7 ft 2 in long and a floor footprint of 49.0 sq ft.

That is the number to tape out on your bedroom floor, not 6 ft 4 in by 6 ft 8 in. Our guide to what size bedroom you need for a king bed runs the full room math, frame plus walkways plus dresser clearance, if you want the complete picture before ordering.

How much of your floor a king bed covers

Floor area is where feet beat inches, because rooms are measured and sold in feet. In a 12 by 12 ft bedroom, 144 sq ft of floor in total:

• Standard king mattress alone: 42.2 sq ft, which is 29 percent of the room.
• The same bed in its 82 by 86 in frame: 49.0 sq ft, which is 34 percent of the room.
• California king mattress: 42.0 sq ft, the same share rounded, just arranged longer instead of wider.

A third of the floor gone before a single nightstand lands. To compare this footprint with typical rooms, see our guide to the average bedroom size. What remains has to hold the walkways: 24 to 30 in of clear space on the sides and at the foot is the working minimum, and our hub guide to the space you need around a bed works through those clearances bed by bed. For a worked example with this exact footprint placed, measured, and furnished, see our layout test of a king bed in a 12 by 12 room.

How many feet is a king size bed?

A standard king size bed is 6.33 ft wide by 6.67 ft long. Written the way tape measures speak, that is 6 ft 4 in by 6 ft 8 in. Neither direction lands on a whole number of feet, which is exactly why this conversion gets looked up so often: a king is not 6 by 7, it is 4 in wider and 4 in shorter than that.

Is a California king longer than a king?

Yes. A California king is 7 ft 0 in long against the standard king’s 6 ft 8 in, a full 4 in longer. The trade is width: at 6 ft 0 in wide it gives back the same 4 in, and its total floor area is a touch smaller, 42.0 sq ft against 42.2 sq ft.

Is a king size bed 6 feet wide?

No. A standard king is 6 ft 4 in wide. The king that is exactly 6 ft wide is the California king, and it pays for that tidy width with its narrower 36 in of space per sleeper. If a listing or a seller describes a king as simply “6 foot,” ask which king they mean and get the inches in writing.

What is the biggest king size bed?

The Alaskan king, at 9 ft by 9 ft (108 by 108 in) and 81.0 sq ft of sleeping surface. It is a specialty, made-to-order size rather than a retail standard, and it needs a very large room: the mattress alone covers more floor than many full bathrooms.

Is a US king the same size as a UK king?

No, and the mix-up wastes real money on bedding. A UK king mattress is 150 by 200 cm, roughly 4 ft 11 in by 6 ft 7 in: about 5 in narrower and 1 in shorter than a US king. UK super king, at 180 by 200 cm, is closer to US width but still not a match. Check the inches on the label, not the word “king,” whenever a bed or sheet set crosses the Atlantic.

Frequently asked questions

Do king sheets fit a California king bed?

No. Fitted sheets are cut to the mattress, so a king sheet built for 76 by 80 in is 4 in too wide and 4 in too short for a 72 by 84 in California king. It will bunch across the width and pop off the corners at the foot. Buy the size named on your mattress label, because the two kings share a name and nothing else.

How much bigger is a king than a queen?

A queen is 60 by 80 in, 5 ft 0 in by 6 ft 8 in, covering 33.3 sq ft. The king keeps the queen’s exact length and adds 16 in (1 ft 4 in) of width, which works out to 8.9 sq ft more sleeping surface. Every inch of the upgrade is width; if your problem is legroom rather than elbow room, a king alone does not solve it and the California king’s 7 ft length is the fix.

Which king size is best for tall sleepers?

Start with the California king: its 7 ft of length suits sleepers up to about 6 ft 6 in with a pillow at the head. Past that, the standard range runs out and the specialty sizes take over, the Texas king at 8 ft 2 in long and the Alaskan king at a full 9 ft. Both are made to order, so factor the wait and the custom bedding into the decision.

Rooms are sold in feet and mattresses are specced in inches, and the gap between those two units is where most king bed mistakes happen. Convert first, tape the frame footprint on the floor second, and order third, and the biggest bed in the house stops being the biggest gamble.

Sources

• Sleep Foundation, King Size Bed Dimensions: standard king 76 x 80 in, California king 72 x 84 in, and the twin XL 38 x 80 in that forms each split king half
• Casper, King Size Bed Frame Dimensions (manufacturer guide): king 76 x 80 in and California king 72 x 84 in, plus the four oversized kings, Wyoming 84 x 84 in, Texas 80 x 98 in, Alberta 96 x 96 in, Alaskan 108 x 108 in
• Purple, Wyoming King Bed size comparison chart (manufacturer): cross-checks every king variant’s width, length, and surface area, including standard king 6,080 sq in and Alaskan king 11,664 sq in
• Sleep Junkie, Biggest Bed Size guide: independent oversized chart matching Wyoming, Texas, Alberta, and Alaskan dimensions, with the note that oversized sizes vary by maker
• Turmerry, King Size Bed Dimensions: standard king confirmed at 6.33 x 6.67 ft (193.04 x 203.2 cm)
• Luxe Mattresses, UK King Size Bed Dimensions: UK king at 150 x 200 cm (4.92 x 6.56 ft) for the US and UK comparison