How to Use the Mattress Size Guide
Choosing a mattress isn't just about the bed frame itself — you also need room to walk around it and make the bed comfortably. Enter your room's width and length, and this tool recommends the largest standard mattress size that still leaves at least 2ft (24in) of clearance on the side and 1ft (12in) at the foot of the bed.
U.S. mattress sizes run from Twin (38×75in) up to California King (72×84in). Twin and Full work well in smaller bedrooms or guest rooms, while Queen (60×80in) is the most popular size for a single adult or couple. King (76×80in) and California King (72×84in) need a larger primary bedroom — California King is a few inches narrower but longer, often preferred by taller sleepers. Measuring your actual room before buying helps avoid a mattress that leaves no space to open dresser drawers or walk comfortably around the bed.
Frequently Asked Questions
A walkway of at least 2ft (24in) beside the bed makes it comfortable to move around and make the bed, and about 1ft (12in) at the foot of the bed is recommended too. This calculator recommends sizes based on that clearance.
A Queen mattress is 60 × 80 in, while a King is 76 × 80 in — 16 inches wider but the same length. California King is 72 × 84 in, narrower but longer than a standard King, popular for taller sleepers.