Mattress Size Calculator

The most expensive mattress mistake is buying a size the room can't take. Enter your room and sleepers and we'll show what fits with real walking clearance.

Sleepers
Queen

60" × 80" — The default for couples — best size-to-price ratio. Leaves about 36" on each side and 64" at the foot of the bed.

Everything that fits this room

Twin Twin XL Full Queen King California King Split King

Mattress dimensions chart

SizeDimensionsMinimum roomBest for
Twin38" × 75"6′ × 9′Single child or a tight guest room.
Twin XL38" × 80"6′ × 9′Adults under 6'5" sleeping alone; dorm standard.
Full54" × 75"7′ × 9′One adult with room to spread out; tight for two.
Queen60" × 80"7′ × 9′The default for couples — best size-to-price ratio.
King76" × 80"9′ × 9′Couples who want space, or share with kids and pets.
California King72" × 84"8′ × 9′Sleepers over 6'2" who trade width for length.
Split King76" × 80"9′ × 9′Two Twin XLs — required for dual adjustable bases.

Got your size? Compare beds in that size in our tested mattress rankings, or read how to choose a mattress. Buying a split king means you also need a dual adjustable base.

FAQs

Guide

Choosing a mattress size: what the calculator weighs

The three things that decide size

  • Room clearance: leave enough walkway on the sides you use to get in and out and to open drawers and doors.
  • Who sleeps in the bed: couples, children or pets joining at night, and whether either partner sprawls.
  • Sleeper height: taller sleepers often need a length of 84 inches (California king) so their feet don't hang off.

Common trade-offs

A king gives each partner roughly the width of a twin, but it can crowd a small bedroom. A queen fits more rooms and costs less for bedding, but couples who wake each other may prefer more space or a split setup.

A California king is longer but narrower than a standard king, so it suits tall sleepers more than couples who want width. Check that sheets, frames and adjustable bases come in the size you choose before buying.

Before you order

Measure doorways and stairwells as well as the room — a hybrid mattress is usually delivered compressed, but a foundation or frame may not be. Confirm the size using the brand's published dimensions, which can vary slightly between models.

Common questions

Is a queen big enough for two adults?

Many couples share a queen comfortably, but each person gets about 30 inches of width. If either partner is broad-shouldered, a restless sleeper or shares the bed with a pet, a king is worth considering if the room allows.

Split king or king?

A split king is two twin XL mattresses side by side, which lets each partner choose a firmness or use a separate adjustable base. A standard king is one surface with no seam.

Continue exploring

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