🛏️ Bed Size Calculator
Pick a standard mattress size to see its exact dimensions and the minimum room size recommended for it.
Standard Mattress Sizes Explained
Mattress sizes are standardized across most U.S. manufacturers, though exact dimensions can vary by an inch or two between brands. This calculator uses the widely accepted standard dimensions for each size.
Twin is the smallest common size, typically used for kids or single sleepers, while California King is the longest option, popular with taller sleepers. Queen remains the most common size for couples due to its balance of space and room fit.
Room size recommendations are general guidelines for comfortable walking space around the bed — always measure your actual room and account for other furniture before buying.
Last reviewed August 2026