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Wyoming King vs California King: The 84-by-84 Square Format Compared

Wyoming King is 7 feet by 7 feet. Cal King is 6 feet by 7 feet. Same length, 12 more inches of width. This page covers when the upgrade from Cal King to Wyoming makes sense, and when it does not.

Last verified April 2026

Wyoming King is one of the oversized custom king formats, sized at 84 by 84 inches (a 7-foot square). It is not an ISPA-standard size. It exists in a small specialty market alongside Alaskan King (108 by 108), Texas King (80 by 98), and Alberta King (96 by 96)[1].

For Cal King buyers wondering whether to go bigger, Wyoming King is the most natural next step: the length stays at 84 inches (so footboard and clearance math is unchanged), but the width jumps from 72 inches to 84. The extra 12 inches of width is the upgrade you are buying.

The size comparison

SizeDimensions (in)Square feetSquare inchesFloor footprint
California King72 x 8442.06,0486 x 7 ft
Wyoming King84 x 8449.07,0567 x 7 ft
Difference+12 in width+7 sq ft+1,008 sq in+1 ft width

Cal King dimensions from the ISPA size schedule[2]. Wyoming King is a non-ISPA custom size produced by specialty manufacturers.


When Wyoming King is the right call

Wyoming King makes sense for households with binding width constraints that Cal King cannot satisfy:

  • Four-person co-sleep is the daily pattern: two adults plus two children regularly share the bed. Cal King provides 72 inches of width; four typical sleepers need 80 to 100 inches. Wyoming King's 84 inches is the practical fit.
  • Two large adults plus a large dog: two adults at 22 inches plus a 70-pound dog at 32 inches occupies 76 inches. Cal King runs out of room; Wyoming gives 8 inches of buffer.
  • Tall sleeper plus partner who values width: the tall sleeper still gets 84 inches of length, and the partner gets the extra width without compromising the height fit.
  • Master bedroom is genuinely large: a 14 by 16 foot or larger master bedroom comfortably absorbs the 7-by-7 footprint with nightstands and walkways. Smaller bedrooms cannot.

When Cal King is still the right call

Stay with Cal King if:

  • Bedroom is under 13 by 13 feet (Wyoming will not fit comfortably)
  • Budget for mattress is under $3,000 (Wyoming starts at $2,500 to $4,500 and rises sharply)
  • You expect to move within 3 to 5 years (Wyoming King is harder to sell or relocate; custom sheets and frames travel with the mattress)
  • Only two people share the bed daily (Cal King width is sufficient for two)
  • The household is averse to specialty-product purchasing (slower delivery, harder-to-source accessories, custom-only frame options)

The accessory ecosystem reality

Wyoming King sheets, comforters, mattress protectors, and bed frames are made by a small number of specialty suppliers. Costs are typically 3 to 5 times the equivalent Standard King accessory. Stocking is special-order in nearly all cases. Replacement cycles for damaged or worn linens become a meaningful logistical issue, not a quick trip to Bed Bath & Beyond.

Plan the entire ecosystem before committing. A Wyoming King mattress without a Wyoming King bed frame, sheets, mattress protector, and at least one spare set is incomplete. Total all-in cost (mattress plus first-set accessories) is typically $4,000 to $7,500 for budget construction, $7,500 to $15,000 for premium.


Bedroom floor-fit math

Bedroom sizeWyoming King (7 x 7 ft) fitCal King (6 x 7 ft) fit
10 x 12 ft (US small master)Does not fit (no walkway clearance)Tight but workable
11 x 13 ftDoes not fit comfortablyComfortable
12 x 14 ft (US median master)Marginal, no nightstand roomComfortable with nightstands
13 x 15 ftWorkable with nightstand limitComfortable
14 x 16 ft (large master)Comfortable with nightstandsComfortable
15 x 17 ft+ (large luxury master)Comfortable with full furniture setComfortable

Walkway clearance assumed at 30 inches per side per Sleep Foundation furniture-planning guidance[3]. Wyoming King requires 13 by 13 minimum, 14 by 14 comfortable.


The honest summary

Wyoming King is the right upgrade from Cal King for a specific household profile: four-or-more daily sleepers, large master bedroom, willingness to invest in specialty-format accessories, and budget at the $4,000+ all-in mark.

For most Cal King buyers, the upgrade math does not justify the cost. The Cal King width (72 inches) handles two-sleeper households comfortably. Adding a third sleeper makes the width tight but workable. Only the fourth sleeper or the large-dog scenario meaningfully overwhelms Cal King and creates a case for Wyoming.

For the larger custom format options, see Alaskan King vs Cal King (108 by 108) and Texas King vs Cal King (80 by 98).


Frequently asked questions

What is a Wyoming King mattress?
A Wyoming King is 84 inches by 84 inches, a 7-by-7 foot square mattress. It is one of several oversized custom king sizes (along with Alaskan King, Texas King, and Alberta King) produced by specialty manufacturers for households needing more width than Standard King provides.
Is Wyoming King bigger than Cal King?
Yes, by area. Wyoming King is 7,056 square inches (49 sq ft). Cal King is 6,048 square inches (42 sq ft). Wyoming has 17 percent more area, almost entirely from the extra 12 inches of width.
Will Wyoming King fit in my bedroom?
Probably not, if your bedroom is under 13 by 13 feet. Wyoming King is 7 feet on each side. With 30-inch walkway clearance on three sides, the minimum bedroom dimension is 12 by 12 feet, and most bedroom layouts need 13 by 13 to accommodate nightstands.
Who makes Wyoming King mattresses?
A small number of specialty manufacturers, including Alaskan King Bed Company, Big Bed Beds, and a handful of regional custom-mattress shops. Wyoming King is not stocked by major chain retailers and is typically a 4 to 8 week custom order.
How much does a Wyoming King cost?
Typically 2 to 4 times the cost of a comparable Standard King. The upfront cost reflects custom manufacturing, smaller production runs, and freight shipping. Accessory costs (sheets, comforters, bed frames) are also significantly higher, often 3 to 5 times Standard King equivalents.

Citations. [1] Wyoming, Alaskan, and Texas King are custom non-ISPA sizes; size definitions from Alaskan King Bed Company published size charts. [2] International Sleep Products Association mattress size schedule (available at sleepproducts.org). [3] Sleep Foundation bedroom-size and walkway-clearance guidance.

Related guides

Alaskan King vs Cal King

108 by 108: the next step up.

Texas King vs Cal King

80 by 98: long over square.

Couples with two children

Where Cal King runs out and Wyoming starts.

Minimum bedroom size

Floor-fit math by mattress format.

Updated 2026-04-27