Some time around 1870 bed manufacturers decided to make bed sizes uniform. Doing that allowed customers to turn away from having beds custom made to buying a bed from any distributor, knowing that all bed designations equaled a specific size. At that time there were two bed sizes: single, which later became known as twin, and double, now known as the full bed.

As Americans grew taller, the standard 74-inch long bed found tall people dangling their feet past the bottom edge of the mattress or hitting their heads on the headboard. By the 1950s, new bed sizes were introduced to combat this growing problem; before long queen and king sizes running 80-inches long hit the market.

Mattress Depth

When considering bed sizes, the mattress depth must enter the equation. Before changes in the industry, all mattresses, regardless of size, were 7-inches deep. When pillow-top mattresses came along, depth increased up to 24 inches. If you're fitting a mattress to a bed frame with a head and foot board, the length and the depth of the mattress matter. The age of the sleeper also affects the comfortable depth of the mattress. Seniors and shorter people have difficulty navigating a high bed frame and its deep mattress.

Queen-Sized Bed

The most favored bed size in America -- the queen bed -- is 60 inches wide and 80 inches long. Couples transitioning from a full-sized bed to a queen may be surprised to learn that the sleeping area each had before the move was about that found in a baby's crib. A queen mattress is 6 inches wider and 5 inches longer than a full-sized mattress and is available in a variety of depths, as well as in inner-coil, air cells and memory foam constructions.

King-Sized Beds

The largest standard-size American bed is the king, also known as the Eastern King. Measuring 76-by-80-inches width to length, the king offers the most sleeping space on the market. It is the equivalent of two twin extra-long beds pushed together. Most king mattresses float atop two individual box springs, making them manageable when moving them up or down stairs.

California King-Sized Beds

Differentiating from an Eastern king, the California king is narrower and longer, measuring 72-by-84 inches.; blame it on the cowboy myth that finds Western men taller. Designed in the early 1960s, the California king bed became a hot fixture in the mega-mansions being designed for Hollywood movie and sport celebrities.

Bedding that fits a California king bed is difficult to find outside of the West coast, most requiring online ordering or purchasing through a store that has outlets on the West coast. The California king is a good size if you are considering adjustable beds that allow multiple head and feet positions.

Larger Beds

Custom bed sizes are available from manufacturers throughout the United States. Whether you want a wider, longer, softer or more firm sleeping experience, specialty fabricators can produce a bed to fit your needs. They also can create specialty shapes, including round and oval beds. Be aware that bedding must also be custom ordered and the beds and bedding cost more than standard bed clothes.