When it comes to cuts of meat, prime rib is like the Rolls Royce—so of course it can be really intimidating to cook. You wouldn’t want to crash and burn something this expensive! The trick: Knowing the right temperature and cook time will give you a tender, juicy roast every time.

Since oven temperatures vary, you’ve gotta have a meat thermometer on hand for this.

Things You'll Need

Cooking Prime Rib

The U.S. Department of Agriculture’s safe food handling guidelines recommend heating meat to a minimum interior temperature of 145 degrees Fahrenheit. To achieve this with prime rib, allow about 10 to 20 minutes per pound, depending on the desired level of doneness. (Smaller roasts cook faster and thicker roasts take longer.)

Begin by searing the roast in the oven at 450 degrees for 15 minutes. Then lower the temperature to 325 degrees, insert the thermometer into the thickest part of the meat, and continue cooking until it reads about 5 degrees from your desired temperature. (The roast will continue to cook for about 20 to 30 minutes after you remove it from the heat.) Here’s a guide to what temperatures to look for:

  • Rare: 120 to 125 degrees
  • Medium rare: 130 to 135 degrees
  • Medium-well: 150 to 155 degrees
  • Well done: 160 degrees