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Mattress sizes, compared by sleeping area

A king sounds only a bit bigger than a queen — but 16 extra inches of width make it about 26% more sleeping area. Compare any two mattress sizes — Twin, Full, Queen, King, California King, or a custom size — by real area, and settle classics like 'is a king bigger than two twins?' once and for all.

It answers questions like 'how much bigger is a king than a queen', 'is a California king bigger than a king' and 'how many twins equal a king' — with dimensions in inches and centimeters, the sleeping area in square feet, and the percentage difference calculated instantly. Set how many of each you're comparing, and two twins against one king is one click away.

Good to know

• A king (76″ × 80″) has about 26% more sleeping area than a queen (60″ × 80″).
• A California king is 4 inches narrower but 4 inches longer than a king — slightly less area, more length.
• Two twins side by side are about the same sleeping area as one king — but with a gap in the middle.

How it works

1. 1Pick the mattress size for option A — or choose Custom and enter exact dimensions.
2. 2Do the same for option B, and set how many of each you're comparing (e.g. two twins vs one king).
3. 3The sleeping areas and the percentage difference are calculated instantly.
4. 4Every size also shows its dimensions in centimeters, so metric shoppers are covered too.

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