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Mattress Size Guide: Twin to California King Compared

Twin, Twin XL, Full, Queen, King, or California King — exact dimensions, who each size fits, and how to pick.

Published 2/10/2025

Standard mattress sizes (inches)

Twin: 38 × 75 — Best for kids, single adults in tight rooms, and bunk beds.

Twin XL: 38 × 80 — Same width as Twin, 5" longer. Common in dorms and for taller solo sleepers.

Full (Double): 54 × 75 — A solo adult who likes extra space, or two adults in a guest room (snug).

Queen: 60 × 80 — The most popular size in the US. Fits two adults comfortably in most bedrooms.

King: 76 × 80 — Two adults plus space for kids or pets. Needs a room of at least 12 × 12 ft.

California King: 72 × 84 — 4" narrower and 4" longer than King. Best for sleepers over 6'2".

How to choose

Measure your bedroom first. Leave at least 2 ft of clearance on each side and at the foot for walking space.

If you co-sleep with kids or pets, size up to a King.

If you're tall (over 6'0"), avoid Full and Twin — both are only 75" long.

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