This depends greatly on the type of comforter you have purchased. I have personally owned down comforters that have been both machine washable and professional clean only. The key is to have a washer that is large enough to properly clean your comforter. Unless the tag specifically notes that the comforter can be put in the dryer, it is best to line dry a down comforter to maintain it fluff. Many comforters also have individually sewn panels, which can shrink disproportionately in the dryer and warp the shape of your comforter.