How Long to Cook Pork Loin Roast (Bone-In, 4–5 lb) in the oven

Specification: 4–5 lb bone-in center cut pork loin roast, scored fat cap, seasoned with herb rub

Target Temp

375°F (190°C)

Radiant Heat

Total Time

1.25–1.75 hours (20 min/lb)

Total Cook Window

Flip Mark

No Flip

Continuous Cook

Internal Safe Temp

140°F (pull) → 145°F (after 15-min rest)

USDA Safe Pull

3-Step Execution Protocol

Preheat & Prep

Preheat oven to 375°F (190°C). Prepare pork loin roast (bone-in, 4–5 lb) (4–5 lb bone-in center cut pork loin roast, scored fat cap, seasoned with herb rub).

Cook

Cook for 1.25–1.75 hours (20 min/lb). Do not flip; allow surface to develop undisturbed.

Check & Rest

Fat cap is golden and crispy; thermometer at thickest point reads 140°F; faint blush-pink center. Confirm internal temperature reaches 140°F (pull) → 145°F (after 15-min rest). Rest for 15 minutes before serving.

Verification Basis & Testing Rig

USDA FSIS 145°F pork standard (2011 revision); tested in GE Profile 30" convection oven with ThermoWorks Thermapen One.

Pro Tip: Pull at 140°F and tent with foil — carryover brings it to 145°F. Score the fat cap in a crosshatch pattern so it renders and crisps evenly.

Related oven Cook Times

Chicken Breast (Boneless, Skinless)

400°F (204°C)20–25 mins

Salmon Fillet (Skin-On, Center Cut)

400°F (204°C)12–15 mins

Baked Potato (Whole Russet)

400°F (204°C)50–60 mins

Bacon (Thick-Cut, Sheet Pan Method)

400°F (204°C)18–22 mins

Pork Chops (Bone-In, 1-inch Thick)

400°F (204°C)18–22 mins

Chicken Thighs (Bone-In, Skin-On)

425°F (218°C)35–45 mins