Mattress sizes can be confusing — especially the difference between Queen and Olympic Queen, or King and California King. Here’s a complete guide to standard mattress dimensions in inches.
| Size | Width × Length | Best For |
| Twin | 38″ × 75″ | Kids, dorms, single sleepers |
| Twin XL | 38″ × 80″ | Tall single sleepers, dorms |
| Full (Double) | 54″ × 75″ | Single adults, guest rooms |
| Queen | 60″ × 80″ | Couples, single sleepers wanting space |
| King | 76″ × 80″ | Couples with kids/pets |
| California King | 72″ × 84″ | Tall couples (over 6 ft) |
Choosing the right size
Twin (38″ × 75″)
For kids under 12 and small adults. Affordable to replace as kids grow.
Twin XL (38″ × 80″)
5″ longer than Twin — for tall single sleepers and college dorms (most use Twin XL).
Full (54″ × 75″)
For single adults who want more width. Tight for couples. Common in guest rooms.
Queen (60″ × 80″)
The most popular size. 6″ wider per person than a Full for couples; very roomy for single sleepers.
King (76″ × 80″)
Each person gets the width of a Twin. The gold standard for couples with kids or pets.
California King (72″ × 84″)
4″ narrower but 4″ longer than King — for couples where one or both partners are 6’2″+ tall.
FAQ
King vs California King?
King is wider; Cal King is longer. If you’re taller than 6 ft, Cal King. If you sleep with kids or pets, King.
Does mattress size affect price much?
Yes — Twin to King doubles the price roughly. The mattress itself costs more in bigger sizes; so do sheets and bases.
Disclosure: Mattresses 4 All earns commission when you buy through our affiliate links.