# Lamb cooking time calculator Enter the weight of your lamb for the roasting time: a leg roasted pink or well done, or a shoulder slow roasted until it falls apart. Source: https://feastflow.co.uk/lamb-cooking-time (FeastFlow free cooking-time guides). Last checked 9 November 2026. The page has a calculator that works out the time for any weight and serving time. ## Leg of lamb cooking times At 180°C (160°C fan), 350°F: **pink** 25 minutes per 450 g (1 lb) plus 25 minutes; **well done** 30 minutes per 450 g plus 30 minutes. The same applies to a half leg. Leg of lamb at 180°C (160°C fan), 350°F: | Weight | Pink | Well done | | --- | --- | --- | | 1 kg (2.2 lb) | 1 h 20 min | 1 h 35 min | | 1.5 kg (3.3 lb) | 1 h 50 min | 2 h 10 min | | 2 kg (4.4 lb) | 2 h 15 min | 2 h 45 min | | 2.5 kg (5.5 lb) | 2 h 45 min | 3 h 15 min | | 3 kg (6.6 lb) | 3 h 10 min | 3 h 50 min | ## Slow-roast shoulder of lamb Roast a shoulder covered at 160°C (140°C fan), 325°F, for about 4 hours for a 2 kg shoulder, plus 30 minutes for each extra kg. Take the foil off for the last 30 minutes. It’s ready when the meat pulls away from the bone with a fork. | Weight | Cooking time | | --- | --- | | 1.5 kg (3.3 lb) | 4 h | | 2 kg (4.4 lb) | 4 h | | 2.5 kg (5.5 lb) | 4 h 15 min | | 3 kg (6.6 lb) | 4 h 30 min | Rest lamb for 20 minutes before carving. ## Questions ### How long to cook a 2 kg leg of lamb? 2 h 15 min for pink at 180°C (160°C fan), or 2 h 45 min for well done. ### What temperature is lamb cooked to? Take it out at 60°C (140°F) for pink, or 70°C (160°F) for well done. It rises a few degrees as it rests. ### How long does a shoulder of lamb take to slow cook? About 4 hours for 2 kg at 160°C (140°C fan), covered with foil. --- Times are a guide: ovens and joints vary. Always check meat with a thermometer before serving. FeastFlow’s times come from British Turkey, AHDB and USDA guidance. FeastFlow also plans a whole meal backwards from serving time, with every dish timed and oven temperatures that don’t clash: https://feastflow.co.uk/