How Long to Cook a 4 lb Pork Loin Roast
A 4 lb pork loin roast needs about 1h 58m at 300 °F / 150 °C. Pull it at 142 °F / 61 °C so carryover takes it to 145 °F, then rest 22 min before carving.
Every method compared
Same 4 lb pork loin, same doneness — only the heat changes. Lean and easy to ruin. Pork loin is not pork shoulder — it goes to 145 °F and comes straight off, no probe-tender stage.
| Method | Pit temp | Cook time | Pull at | Rest |
|---|---|---|---|---|
| Reverse Sear | 300 °F / 150 °C | 1h 58m | 142 °F | 22 min |
| Smoker (Low & Slow) | 225 °F / 110 °C | 3h 6m | 142 °F | 22 min |
Pull temps differ per method on purpose: a 450 °F grill drives far more residual heat into the meat than a 225 °F pit, so the same final temperature needs a different pull point.
Adjust these numbers for your exact cut →Free interactive calculator · works offline · installs to your home screenRecommended Tools for Perfect Results
You cannot cook to temperature without measuring temperature. These are the two tools that change results the most.
Wireless Bluetooth Meat Thermometer
Leave-in probe with phone alerts. The single upgrade that ends dry brisket and grey steak.
on Amazon
Pink Butcher Paper (Unwaxed, 18")
Beats foil for the Texas Crutch: pushes through the stall while keeping the bark crisp.
on Amazon
Instant-Read Digital Thermometer
Two-second readings for spot checks and for probing brisket for tenderness.
on Amazon
As an Amazon Associate we earn from qualifying purchases. Prices and availability are set by Amazon and may change.
Other sizes
Download the printable temperature chart
Every temperature on this site on one page — beef, pork, poultry, seafood and low & slow, plus the carryover rule. Print it and tape it inside your grill lid.
One email with the chart, plus the occasional seasonal guide. Unsubscribe in one click, no spam. Prefer not to subscribe? Download it directly.
Frequently Asked Questions
How long does a 4 lb pork loin take?
About 1 hour 58 minutes at 300 °F, plus 22 minutes of rest. Weight is only a guide — start probing early, because roast shape matters as much as weight.
What internal temperature should it reach?
145 °F / 63 °C final. Pull it at 142 °F: a roast this size carries over about 3 °F while resting.
How long should it rest?
22 minutes. Tent it loosely with foil — a large roast holds heat for a surprisingly long time.