Mattress Sizes and Dimensions: Which Bed Size Is Right for You?
Short answer: a Queen (60″ × 80″) suits most couples and most bedrooms. A King (76″ × 80″) gives each sleeper as much width as a Twin, if your room has space. Tall sleepers should stick to the 80-inch lengths (Twin XL, Queen, King) or the 84-inch California King. The chart and room calculator below show what fits.
Mattress size chart (US standard sizes)
| Size | Width × length (inches) | Width × length (cm, approx.) | Width per person if shared | Usually best for |
|---|---|---|---|---|
| Twin | 38 × 75 | 97 × 191 | Not for two | Kids, bunk beds, small guest rooms |
| Twin XL | 38 × 80 | 97 × 203 | Not for two | Teens, tall single sleepers, dorm rooms |
| Full (double) | 54 × 75 | 137 × 191 | 27″ each | One adult who wants room to spread out |
| Queen | 60 × 80 | 152 × 203 | 30″ each | Most couples; the most common primary-bedroom size |
| King | 76 × 80 | 193 × 203 | 38″ each (same as a Twin) | Couples who want space, kids or pets joining in |
| California King | 72 × 84 | 183 × 213 | 36″ each | Tall sleepers; long, narrower rooms |
| Split King | Two 38 × 80 halves (76 × 80 total) | Two 97 × 203 | 38″ each, separate mattresses | Couples with different firmness needs, or a split adjustable base |
These are the standard US dimensions published in mattress makers’ size charts (checked October 17, 2026). Real mattresses can come in up to about an inch narrower or shorter, so check the listing’s exact measurements.
Queen vs King vs California King
- Queen vs King: both are 80″ long. A King is 16″ wider, which gives each person 38″ of width instead of 30″. If you or your partner move a lot at night, that extra width makes a real difference.
- King vs California King: a King is 4″ wider (76″ vs 72″). A California King is 4″ longer (84″ vs 80″). So a California King is not just a bigger King. Pick it only if length matters more than width.
- Full vs Queen: a Full is 6″ narrower and 5″ shorter. Two adults get only 27″ each, about the width of a crib mattress. That’s fine for one person, and tight for two.
How long should your bed be?
A simple test: lie down and stretch out with a pillow. If your feet reach the end, the bed is too short. Pillows, a slight bend at the knees and sliding down at night all use up length. So if you are around 6 feet or taller, skip the 75″ sizes (Twin and Full). Choose an 80″ bed (Twin XL, Queen, King), or the 84″ California King if you are well over 6 feet.
Will it fit your room?
Measure the room wall to wall, then leave space to walk around the bed. Many designers plan for about 24–36 inches of clear floor on each side you use and at the foot of the bed. Also allow for nightstands, a dresser you need to open, and doors that swing in.
Room fit calculator
Enter your room size and the walkway you want. The bed goes against the headboard wall, with space on both sides and at the foot.
| Room width (wall the headboard goes on), feet | |
| Room length, feet | |
| Walkway on each side and at the foot, inches |
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Example: in an 11 × 12 ft room (132″ wide) with a 30″ walkway, a Queen fits (60″ + 2 × 30″ = 120″). A California King just fits (72″ + 60″ = 132″). A King doesn’t (76″ + 60″ = 136″), unless you accept walkways of 28″ (76″ + 56″ = 132″).
What else has to match the size
- Sheets: buy sheets in the exact size. King and California King sheets don’t swap, and neither do Twin and Twin XL. Check the fitted sheet’s pocket depth against your mattress height, plus any topper or protector.
- Frame or base: the frame must be the same size as the mattress. Check how far apart the slats are and whether the frame needs a center support. For a Split King on an adjustable base, you need two Twin XL bases or one split base.
- Getting it inside: measure doorways, stair turns and halls if the mattress arrives full size. A mattress that comes compressed in a box is much easier to carry upstairs.
- Bedding: comforters and duvets are often sold as Full/Queen or King/California King. A slightly oversized comforter usually looks better than an exact match.
Quick checklist before you buy
- Your height (and your partner’s): 75″ or 80″+ length?
- Width per person you want: 27″ (Full), 30″ (Queen), 36–38″ (California King/King)
- Room measured, with walkway, nightstands and door swing
- Doorways and stairs measured, or a boxed mattress
- Frame or base in the same size, and sheets that fit the mattress depth
Shop by size on Amazon
Choose your size on each listing and check the exact measurements, trial and return terms.
Keep reading
Not sure how firm to go? Read the mattress firmness guide. Or browse hybrid mattresses, bed frames and sheets & linen.
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