The best way to tell if your roast is done is to use a meat thermometer. Roasts are too big to tell by just touching it, like you can with steaks. You do not want to cut into the roast to check for doneness because it will lose its juices. Insert a meat thermometer thru the side of the roast (not the top) and into the center of the roast. For medium rare, take out roast at 125ºF.