A good width for a dining table depends on factors beyond your style as a host -- predominantly, the room's size and shape. Square, oval, rectangular and round tables come in various standard widths, so typically there's one for any space, even a seemingly awkward one.
Standard Dining Table Sizes
Although standard dining table height -- 30 inches -- typically doesn't change regardless of the tabletop shape and size, widths vary greatly. Round table diameters, for instance, often increase in 1-foot increments, from 3 to 10 feet. The smallest circular table seats two to three people comfortably, and the largest seats 12 to 15. Square tables range from about 3 to 8 feet wide, while rectangular and oval tables come in roughly 2 1/2- to 4 1/2-foot widths, and up to 10 feet in length.
A Proportional Shape
Round tables suit square or oddly shaped dining rooms and maximize seating in small spaces because of the generous elbow room that this shape affords. A long, narrow dining room benefits from a rectangular table with a couple of leaves for extra length -- a 3-feet-wide by 6-feet-long table seats six to eight diners, but with just 6 more inches of width and 2 additional feet of length, it can handle two extra chairs. Contemplate using a square table in a long room if you plan to also furnish the space with a hutch or sideboard on one end. An oval table has a more traditional vibe but otherwise suits similarly shaped rooms as its rectangular counterpart.