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Saatva Classic. From $1,095
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A king size mattress is the widest standard option available -- 76 inches wide and 80 inches long. If you share your bed and want each person to have as much space as a twin mattress, king is the answer.
King Size Dimensions
A king mattress measures 76 inches wide by 80 inches long (approximately 6'4" x 6'8"). That gives each person in a couple 38 inches of personal space -- the same width as a twin bed.
Budget Pick
Sweetnight Twilight Hybrid — From $329
Medium-firm 6/10, pocket coils, HSA eligible. 100-night trial.
King vs Other Sizes
| Size | Dimensions | Width Per Person (couple) |
|---|---|---|
| Queen | 60" x 80" | 30" |
| King | 76" x 80" | 38" |
| Cal King | 72" x 84" | 36" |
Best King Mattresses 2026
Best Budget King: Sweetnight Breeze King
The Sweetnight Breeze in king delivers cooling hybrid performance at $699 -- PCM-infused foam + individually wrapped coils, 365-night trial.
Best Mid-Range King: Puffy Lux King
The Puffy Lux King at $1,699 uses 5 foam layers including climate-adaptive cover and firm support base. Lifetime warranty, 101-night trial. Strong for couples who need motion isolation.
Best Premium King: Amerisleep AS3 King
The Amerisleep AS3 King ($1,699) uses plant-based Bio-Pur foam that sleeps cooler than standard memory foam. 20-year warranty, 100-night trial.
Frequently Asked Questions
What are the exact king mattress dimensions?
A standard king mattress is 76 inches wide by 80 inches long. This is also called an Eastern King to distinguish it from a California King (72" x 84").
Is a king mattress worth it for couples?
Yes -- a king gives each partner 38 inches, the width of a twin bed. If either partner is a restless sleeper, shares the bed with a pet, or simply wants more room, the extra cost (typically $200-$500 over queen) is worth it.
What's the difference between king and California king?
King (76" x 80") is 4 inches wider; California King (72" x 84") is 4 inches longer. Choose king for more width; choose Cal king if either sleeper is over 6'2".
Frequently asked questions
What should I know about alaskan king size sheets?
Alaskan king sheets fit a 108" x 108" mattress — a square, 9-foot on each side. Not stocked by mainstream retailers; order from Alaskan King Bed Co, Big Mattress Co, or custom linen makers. Expect $400+ per sheet set. Cal king or king sheets won't fit — the Alaskan needs dedicated bedding.
What should I know about cal king size?
A standard king measures 76" x 80" and a California (cal) king measures 72" x 84". King is 4 inches wider, cal king is 4 inches longer. Choose cal king if sleepers are taller than 6 feet or the bedroom is longer than wide; choose king for couples who need extra shoulder space.
What should I know about cal king mattress size?
A standard king measures 76" x 80" and a California (cal) king measures 72" x 84". King is 4 inches wider, cal king is 4 inches longer. Choose cal king if sleepers are taller than 6 feet or the bedroom is longer than wide; choose king for couples who need extra shoulder space.
Frequently asked questions
What should I know about alaskan king size sheets?
Alaskan king sheets fit a 108" x 108" mattress — a square, 9-foot on each side. Not stocked by mainstream retailers; order from Alaskan King Bed Co, Big Mattress Co, or custom linen makers. Expect $400+ per sheet set. Cal king or king sheets won't fit — the Alaskan needs dedicated bedding.
What should I know about cal king size?
A standard king measures 76" x 80" and a California (cal) king measures 72" x 84". King is 4 inches wider, cal king is 4 inches longer. Choose cal king if sleepers are taller than 6 feet or the bedroom is longer than wide; choose king for couples who need extra shoulder space.
What should I know about cal king mattress size?
A standard king measures 76" x 80" and a California (cal) king measures 72" x 84". King is 4 inches wider, cal king is 4 inches longer. Choose cal king if sleepers are taller than 6 feet or the bedroom is longer than wide; choose king for couples who need extra shoulder space.