How long to cook prime rib per pound?

At 325°F, plan 13-15 minutes per pound for medium-rare, 15-17 for medium. Always use a meat thermometer — pull at 130°F for medium-rare, then rest 15-20 minutes.

What temperature to cook prime rib?

325°F is the standard oven temperature for prime rib. Some recipes use a high-heat sear at 450°F for 15-20 minutes, then reduce to 325°F for the remainder.

How much prime rib per person?

Plan about 3/4 to 1 pound of bone-in prime rib per person. A 6-pound roast serves 5-6 people generously.

Prime Rib Cook Time Calculator

Calculate exact prime rib cooking time by weight and desired doneness at 325°F.

Whiskers says

At 325°F, plan 13-15 minutes per pound for medium-rare. Pull at 130°F internal and rest 15-20 minutes — carryover cooking does the rest!

🥩 Prime Rib Cook Time

Weight (lbs)

Bone-in standing rib roast

Doneness

6 lb prime rib — Medium-Rare

1h 18m – 1h 30m

At 325°F · Pull at 130°F internal · Rest 15-20 min

Formula: 6 lbs × 13-15 min/lb = 78-90 min total at 325°F

Use a meat thermometer — it's the only reliable way. Pull the roast at 130°F and let it rest 15-20 minutes. Carryover cooking will raise the temp another 5-10°F. A 6 lb roast feeds 5-6 people generously.

📋 Prime Rib Timing at 325°F