King Mattress Dimensions
The king mattress (also called Eastern king) is the widest standard size at 76 inches wide by 80 inches long. Each person gets 38 inches of sleeping space — the equivalent of their own twin mattress.
How big is a king mattress?
A king mattress is 76 inches wide and 80 inches long — the widest standard mattress. Each sleeper gets 38" of personal space (equal to a twin bed).
Dimensions
Doorway Fit Analysis
Will a King Mattress fit through a standard doorway?
Will fit through with proper technique
- •Smallest dimension (thickness): 10"
- •Standard interior door: 32"
- •Standard exterior door: 36"
Fits with room to spare
Fits with room to spare
Fits with room to spare
Mattress Size Comparison
| Size | Width | Length | Area |
|---|---|---|---|
| Twin | 38" | 75" | 2,850 sq in |
| Twin XL | 38" | 80" | 3,040 sq in |
| Full/Double | 54" | 75" | 4,050 sq in |
| Queen | 60" | 80" | 4,800 sq in |
| King ← | 76" | 80" | 6,080 sq in |
| Cal King | 72" | 84" | 6,048 sq in |
Frequently Asked Questions
Will a king mattress fit through a standard doorway?
It's tight but possible. At 76" × 80" × 10", the 10" side passes through a 32" door, but the 76" width makes cornering difficult. Use the front/exterior door (36") and remove door stops for best results.
What is the minimum room size for a king bed?
A king bed needs at least a 12' × 12' room (144 sq ft) for comfortable walkways and nightstands. In a 10' × 12' room it will fit but feel cramped.
What is the difference between king and California king?
King is 76" × 80" (wider); Cal king is 72" × 84" (narrower but longer). King is better for couples who want more width; Cal king suits taller individuals who need extra length.
Related Mattress Sizes
Related Calculators
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