Treat the result as a starting point — usually within 10–20% of the real time. Oven calibration, meat thickness, fridge-cold vs room-temperature start, bone-in vs boneless, and convection vs conventional all shift the actual time. Always finish on internal temperature using a probe thermometer.

See the helper line under the rate input. Quick reference: beef 30 / 40 / 45 for rare / medium / well-done, chicken 35, turkey 25 (the lowest because whole birds cook fast), pork loin 50, lamb 45, duck 45. All assume a 180 °C / 350 °F oven and a 1–4 kg roast.

A whole turkey is denser-shaped and cooks more uniformly than a chicken, and the rate is tuned for typical 4–7 kg birds. Smaller turkeys behave more like chickens and need a slightly higher rate.

Yes — bone slows heat penetration through the meat. Add roughly 5 minutes per kg for bone-in. Spatchcocking a chicken or turkey has the opposite effect and shaves 20–25% off the time.

Either drop the oven temperature by 20 °C and keep the same time, or keep the temperature and trim the time by about 10%. Convection cooks more evenly but faster — check earlier with a thermometer.

Divide pounds by 2.2046 to get kilograms (e.g. 5 lb ÷ 2.2 ≈ 2.27 kg) and enter that. The "Weight in pounds" output mirrors your input back in lb so you can sanity-check the conversion.

Yes — let the roast sit on the counter for 30–60 minutes before it goes in. A fridge-cold roast can add 10–15% to the total time and tends to cook unevenly (outside overdone before the centre is ready).

Carry-over cooking. Internal temperature keeps rising 3–5 °C in small roasts and up to 8 °C in larger ones while resting. Pull the roast a few degrees before the target temperature so it finishes on the bench.