What Is a King Bed?
A king bed measures 76 inches wide by 80 inches long (193 cm x 203 cm) and is the widest standard mattress size in the United States. Each sleeper on a king gets approximately 38 inches of personal width—the equivalent of a twin bed each. It is the size for couples who want maximum space, families who co-sleep with children or pets, and anyone furnishing a larger primary bedroom.
A king is sometimes called an "Eastern king" to distinguish it from the California king, which trades width for length.
Avocado Recommends: Choose a King if you share the bed nightly and your room is at least 12 × 10 feet — each partner gets a full 38 inches, the width of an entire Twin. If you and your partner want different firmnesses or use adjustable bases, order a split king instead: two Twin XLs on a king frame, each side independent. And measure your stairwells before delivery — boxed shipping fits through tight turns, but an expanded mattress can't be recompressed.
King Bed Dimensions at a Glance
Mattress Size | Dimensions (inches) | Ideal For | Avocado Option |
Queen | 60" x 80" | Couples, most bedrooms | Every adult model, including the Green Mattress and Luxury Organic Mattress |
King | 76" x 80" | Couples who want maximum width, co-sleeping families | Every adult model, including the Green Mattress and Grand Luxe |
California King | 72" x 84" | Sleepers over 6'2", long rooms | Every adult model, including the Green Mattress and Grand Luxe |
Split King | Two 38" x 80" (Twin XL) | Different firmness preferences, adjustable bases | Available across the lineup, including the Green Mattress and Luxury Organic Mattress |
Pro Tip: A king and a queen are the same length (80 inches). The 16 extra inches are all width—exactly what co-sleeping families and restless sleepers need.
Ideal Room Size for a King Bed
We recommend a minimum room size of 12 x 10 feet for a king bed, with 12 x 12 feet or larger for a comfortable layout with nightstands, a dresser, and clear walkways on all sides. In smaller rooms, a king dominates the floor plan; measure the room and account for existing furniture before ordering.
One more measurement matters at this size: doorways, hallways, and stairwells. A one-piece king is the hardest mattress to maneuver into a home. If your route includes a narrow staircase or tight corners, a split king—two Twin XL mattresses—delivers the same footprint in two manageable pieces.
Who Is a King Mattress Best For?
A king bed is an ideal option for:
Couples who want maximum personal space—38 inches each, the width of a twin per person.
Families who co-sleep with young children or pets.
Restless or light sleepers, where extra distance reduces nighttime disturbance.
Larger primary bedrooms, where a queen can look undersized.
Ready to compare? Explore Avocado's certified organic mattresses in King.
King vs. Queen: Which Should You Choose?
A king is 16 inches wider than a queen at the same length (76" x 80" vs. 60" x 80").
Choose a queen for bedrooms under 12 x 12 feet or couples comfortable with 30 inches of personal space each.
Choose a king for co-sleeping families, restless sleepers, and bedrooms with room to spare.
For the full comparison from the queen's side, see our guide to Queen Bed Dimensions.
King vs. California King: Which Should You Choose?
The California king (72" x 84") is 4 inches narrower and 4 inches longer than a standard king. It is not a bigger king—it is a different tradeoff.
Choose a king for maximum width: co-sleeping, pets, restless partners.
Choose a California king when height is the deciding factor—sleepers over 6'2"—or when the room is long rather than wide.
Important: King and California king bedding are not interchangeable. Sheets, protectors, foundations, and adjustable bases sized for one will not fit the other. Check dimensions before buying accessories. For the complete breakdown of the longer size, see our guide to California King Bed Dimensions.
Split King: Two Mattresses, One Bed
A split king is two Twin XL mattresses (38" x 80" each) placed side by side, producing the same 76" x 80" footprint as a standard king. It solves three problems a one-piece king cannot:
Different firmness preferences. Each sleeper chooses their own mattress. One side Extra Firm, the other Ultra Plush—no compromise.
Independent adjustability. A split king is the standard configuration for dual adjustable bases, where each side raises and lowers separately. Avocado's adjustable bases are available in split king.
Delivery logistics. Two Twin XL mattresses navigate stairs and doorways a one-piece king cannot.
Avocado offers split king configurations across our mattress lineup. For the complete breakdown, see: What Is a Split King Mattress?
How Much Does an Organic King Mattress Weigh?
An Avocado king weighs roughly 110 to 186 pounds depending on the model, from the Eco Organic Mattress (110 lbs) to the Ultra Plush Luxury Organic Mattress (186 lbs). Natural latex is denser than polyurethane foam—that density is part of why it holds its structure for decades while synthetic foams soften and sag.
Because of that weight, king and California king sizes ship via Doorstep Delivery rather than standard parcel carriers, and optional In-Home Delivery & Setup is available in the continental U.S. Every Avocado mattress has handles stitched in for positioning, and should be rotated head-to-foot every six months—never flipped. For exact dimensions and weights by model, see: What Mattress Size Is Best for Me?
What Foundation Does a King Latex Mattress Need?
At 76 inches wide, a king mattress requires more than a sturdy frame—it needs center support: a center rail with legs to the floor, or a platform engineered to prevent sagging at the middle of the span. This matters more for organic latex mattresses, which weigh substantially more than foam. Avocado's FSC-certified wood bed frames, foundations, and adjustable bases are all built for the weight.
Why Choose an Organic King Mattress
A king is the largest sleep surface in the house—which makes it the largest single deposit of material in your bedroom. Whatever a mattress is made of, a king contains the most of it. Most conventional kings are built around polyurethane or memory foam, a petroleum-derived material, along with chemical adhesives and synthetic fabrics that can emit volatile organic compounds (VOCs) into bedroom air. At king scale, the materials question is at its biggest.
Avocado king mattresses are made instead with GOTS-certified organic cotton, GOLS-certified organic latex, and organic wool—without polyurethane foam, chemical flame retardants, or fiberglass.
Size also raises the stakes on durability. A king-size mattress is the most expensive standard mattress to buy and the largest to replace, ship, and dispose of. Avocado mattresses are backed by warranties of up to 25 years, and an independent Life Cycle Assessment found a single Avocado mattress generates approximately 47% less CO₂e over 25 years than the 2.5 conventional mattresses needed to cover the same period. The longer a king lasts, the less often the biggest mattress in the house ends up in a landfill.
Certified at the Finished-Product Level
Every Avocado mattress, including every king, is certified organic under GOTS at the finished-product level. GOTS certifies the entire mattress as it arrives in your home—not individual components inside an otherwise conventional product. It is one of six independent finished-product certifications our mattresses hold:
GOTS — organic integrity from farm through finished product.
OEKO-TEX® Standard 100, Class I — tested against the most restrictive human-ecological thresholds, the category designed for products intended for babies and toddlers.
MADE SAFE® — screened against more than 6,500 known or suspected harmful substances.
EWG Verified® — full ingredient transparency and health-based screening.
GREENGUARD Gold — certified against strict limits for VOC emissions in indoor environments.
UL® Formaldehyde-Free — independently validated to contain no added formaldehyde.
Explore our certifications to see what each standard verifies.
Avocado Mattresses Available in King
Nearly every Avocado mattress model is available in King and California King, from the Eco Organic Mattress to the Grand Luxe, with firmness options from Extra Firm to Ultra Plush, and split king configurations across the lineup.
Summary: King Mattress Size Overview
A king mattress measures 76 by 80 inches—the widest standard size, giving each sleeper the width of a twin. It suits co-sleeping families, restless partners, and bedrooms at least 12 x 10 feet, with a split-king option that adds independent firmness and adjustability.
Choosing a certified organic king means the largest material presence in your bedroom has been independently verified—from the soil the cotton grew in to the finished product in your home—and built to last decades rather than years.
Sleep Better, Naturally: Explore Avocado's Organic Mattresses
FAQ
What are the dimensions of a king bed?
A standard U.S. king mattress measures 76 inches wide by 80 inches long.
What is the difference between a king and a California king?
A king (76" x 80") is 4 inches wider; a California king (72" x 84") is 4 inches longer. King suits couples who want width; California king suits sleepers over 6'2". Bedding for one will not fit the other.
Do two Twin XL mattresses equal a king?
Yes. Two Twin XL mattresses (38" x 80" each) side by side match a standard king's 76" x 80" footprint. This configuration is called a split king.
What room size do I need for a king bed?
A minimum of 12 x 10 feet, with 12 x 12 feet or larger recommended for comfortable clearance and furniture.
How much does an organic king mattress weigh?
Avocado king mattresses weigh roughly 110 to 186 pounds depending on the model, and ship via Doorstep Delivery rather than standard parcel carriers.
Is a king or split king better for couples?
A one-piece king offers a unified surface. A split king lets each sleeper choose their own firmness and adjust their side independently on a dual adjustable base. Couples with different firmness preferences are usually better served by the split king.