This calculator estimates oven roasting time for beef, lamb, pork, chicken and turkey based on weight and how well done you want it, then shows the safe internal temperature to confirm with a thermometer. It is for home cooks planning a Sunday roast or holiday joint.
How it works
Times are based on standard guidelines at 180°C / 350°F: a per-500g rate for the chosen meat and doneness, plus a fixed base time. The total is:
time = (weight ÷ 500g) × minutes-per-500g + base
Per-500g rates are roughly 15 (rare), 20 (medium) and 25 (well) minutes for beef and lamb; 30–35 minutes for pork; and about 20 minutes for whole poultry. Base time is 15 minutes for joints and 20 for whole birds. Doneness also sets the target internal temperature.
Example
A 1.5 kg beef joint cooked medium:
(1500 ÷ 500) × 20 + 15 = 3 × 20 + 15 = 75 minutes. Pull it at an internal temperature of 63°C / 145°F and rest before carving.
| Meat | Per 500 g | Safe internal temp |
|---|---|---|
| Beef / lamb (medium) | 20 min | 63°C / 145°F |
| Pork | 30–35 min | 63°C / 145°F |
| Chicken / turkey | ~20 min | 74°C / 165°F |
Times are estimates — oven calibration, bone and starting temperature all matter, so always confirm doneness with a probe thermometer. All estimates are calculated locally in your browser.