Cooking & Kitchen

Roast Cooking Time Calculator

Roasting time scales with weight: multiply the weight by the minutes per 500 g for your chosen doneness, then rest the meat before carving.

The result gives the roasting time for your roast weight, plus the resting time to allow before carving.

Formula

Roasting time = (weight / 500) x minutes per 500 g. Resting time is about 20% of roasting time.

How it works

Minutes per 500 g varies by meat and doneness — rare beef needs far less than well-done pork. Check your meat's guide value and use a thermometer for certainty.

Resting matters: juices redistribute as the meat cools slightly, so carving too early spills them onto the board instead of keeping them in the meat.

Worked example

For example, (1500 ÷ 500) × 25 = 75 minutes of roasting, plus about 15 minutes of resting.

FAQs

What temperature should the centre reach?
It depends on the meat: beef rare is about 52 °C, medium 60 °C, while pork and poultry need higher, food-safe temperatures.

Does shape matter as much as weight?
Yes. A flat, wide joint cooks faster than a compact round one of the same weight, since heat reaches the centre sooner.

Why rest the roast?
Resting lets juices settle back through the meat, so slices stay moist instead of leaking onto the board.

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