How much size of Area Rug I should buy?

If you want an area rug that is round, the best guideline is to go with a foot and a half on either side of it to the closest wall, So in this case, a circular area rug around 8ft. in diameter. This guide line is almost the same for rectangular rugs. About 8 - 8.5 ft. wide but about 10 - 11.5 ft long.