December 17, 2019
Filed under: Mattress Guide

King size mattresses are built to industry standard dimensions. King beds are approximately 76 inches wide by 80 inches long. California king mattresses are a bit longer measuring 72 inches wide by 84 inches long. Use the table below to compare mattress sizes.

Width x Length

Standard Size

38″ x 74.5″


38″ x 79.5″

Twin XL

53″ x 74.5″


60″ x 79.5″


76″ x 79.5″


72″ x 83.5″

California King

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