Butterflied leg of lamb Cooking Time Calculator

Butterflied leg of lamb Cooking Time Chart

Weight	Cooking time	Internal temp
2 lb	37 min	136°F
3.5 lb	58 min	136°F
4.5 lb	1 hr 11 min	136°F

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How This Calculator Works — Formula & Method

Source: standard US roasting guidance · applied deterministically · verify with a thermometer

Constant	Value	Source
Time per lb	14 min/lb (range 12–20/500 g)	US roasting guides
Internal target	136°F / 58°C	USDA / thermometer
Base offset	10 min	Standard
Oven	430°F sear for 20 min, then 400°F	Method
Resting	10 min	Best practice

— Butterflied leg of lamb cooking time —
total_min = min_per_500g × (weight_lb × 453.592 / 500) + base_offset
range = [lo_per_500g … hi_per_500g] × (weight / 500) + base_offset
conventional_oven = fan_temp + 10–20°C (same time)
celsius = derived table from °F
— algorithm —
lookup(meat, cut, doneness) → point_estimate → guidance_range
→ internal_target_temp → verify_with_thermometer()

Public roasting guidance applied deterministically — this is not a food-safety authority. Always cook to the stated internal temperature, measured with a meat thermometer.