Roasting Time Calculator
Estimate roasting time and oven temperature by meat type and weight.
Please note: Cooking guides only. Times and temperatures vary with oven calibration, altitude, starting temperature and cut. For anything where safety matters — poultry, pork, sous vide, preserving — use a probe thermometer and follow your national food safety guidance rather than a calculated time.
What the Roasting Time Calculator does
Roasting guides work from weight because heat has to travel to the centre, and that distance grows with the size of the joint. The fixed addition covers the initial heating of the surface, while the per-kilogram rate covers the journey inwards.
Formula
Time = Weight in kg × Minutes per kg + Fixed minutesChicken: 45 min/kg + 20 min at 200 °CBeef medium: 55 min/kg + 25 min at 190 °C
Inputs explained
| Input | Unit | Required | Notes |
|---|---|---|---|
| Meat and doneness | one of 9 options | Yes | — |
| Weight | number | Yes | Accepts more than 0. |
| Weight unit | one of 4 options | Yes | — |
| Resting time | minutes | Optional | Accepts 0 or more. |
| Extra for stuffing | minutes | Optional | Accepts 0 or more. |
How to use it
- Choose Meat and doneness and Weight unit.
- Enter Weight.
- Optionally add Resting time and Extra for stuffing.
- Select Calculate.
Worked example
A 2 kg chicken.
- Meat
- Chicken
- Weight
- 2 kg
- Rest
- 20 min
2 × 45 + 20 = 110 minutes, so 1 h 50 min at 200 °C. With a 20 minute rest, allow 2 h 10 min in total. Check the thigh reaches 74 °C.
Frequently asked questions
Can I trust a time-based calculation for chicken?
Use it to plan, not to judge doneness. Poultry must reach 74 °C at the thickest point, and only a probe thermometer confirms that.
Why does a bigger joint not take proportionally longer?
Because heat travels in from the surface. Doubling the weight less than doubles the distance to the centre, which is why the fixed addition sits alongside the per-kilogram rate.
Method and sources
Method. Estimated time from weight at the minutes-per-kilogram convention for the cut and doneness selected, plus a fixed allowance and a resting period.
Assumptions
- The joint starts near room temperature, is a regular shape, and the oven holds its set temperature.
Limitations
- Time is an estimate for planning, never a test of doneness. Weight-based rules ignore thickness, bone, shape and starting temperature, all of which move the real time substantially.
- For any meat where undercooking carries risk — poultry and minced meats in particular — internal temperature measured at the thickest point is the only reliable check, and it is the temperature your national food-safety authority publishes that governs, not this estimate.
- Carry-over cooking continues to raise internal temperature during resting, so removing at the target temperature overshoots it.
Sources
- Your national food-safety authority's published safe internal cooking temperatures — Varies by country. The doneness and safety decision this calculator deliberately does not make. It estimates duration; only a measured internal temperature establishes that food is safe.