Prime Rib Calculator

Calculate the perfect cooking time for your prime rib roast based on weight, desired doneness, bone type, and cooking method. Get accurate cooking times, temperature targets, and serving estimates for a restaurant-quality prime rib.

Prime Rib Serving Size:
Bone-in: 1 lb (454g) per person
Boneless: 0.5-0.75 lb (227-340g) per person

Cooking Time (325°F):
Rare: 15-17 min/lb
Medium: 20-22 min/lb
Example: 8 guests, bone-in

Prime rib needed = 8 × 1 lb = 8 lbs
= 3-4 bone roast

Cooking time (medium-rare):
8 lbs × 18 min/lb = 144 minutes (2.4 hours)