A traditional-style rug sometimes has a central round or oval design known as a medallion. This design element can be found in rugs of all shapes and sizes. If you plan to center your round coffee table on a rug, the medallion makes it easy to locate the center. This combination can result in a pleasing decorative effect. However, if the coffee table is off-center, the opposite effect will result.
Using a round rug with a round coffee table creates the effect of two concentric circles if the coffee table is exactly centered on the rug. However, it is not necessary to center the table on the rug if it does not have a distinct central pattern, such as a medallion. Placing the table off-center and asymmetrically balancing the other furniture around the rug achieves a pleasing arrangement. Be sure the rug is large enough so that the table does not look as though it is about to slide off the edge of the rug.
An eight-sided or octagonal rug complements a round coffee table well. If the rug is only a few feet larger than the table, it is best to center the table on the rug. Otherwise, offset the table as with a round rug, provided there is no distinct central pattern. The angular edges or border of the rug still create a pleasing contrast to the smooth curve of the table.
The contrast of shapes created by placing a round coffee table on a square or rectangular rug has timeless appeal; and ready-made rectangular rugs are still the easiest to find. For easy placement, look for a rug that has an allover pattern or a decorative border. It is not necessary to center the table on a square or rectangular rug as long as the rug is large enough to leave a margin of a few feet all the way around the table.