Serving Size Calculator
How much food to cook and buy for a crowd from your own amount per person, with extra for seconds and trim divided out properly, or how many portions you have.
Result
To cook: 8.25 lbEstimate
The amount per person is yours: no serving size is stored, because published figures disagree.
- To buy, before trim
- 8.25 lb (132 oz, 3.74 kg)Estimate
https://calcgallery.com/recipe/serving-size-calculator/
Results are arithmetic on the figures you enter. Cooking times are estimates: ovens, cuts and starting temperatures vary, so check doneness with a thermometer. Safe temperatures are the USDA's; guidance differs by country, so check your own. Read the full disclaimer
How to use the Serving Size Calculator
- Choose whether to work out how much to cook and buy, or how many portions you already have, and whether you measure by weight or volume.
- Enter the number of people and your own amount per person, with any extra for seconds and the share lost to trim, bones or peel.
- Read how much to cook and how much to buy. Add the total cost, under more options, to see the cost per serving.
The arithmetic
to cook = amount per person × people × (1 + extra for seconds)to buy = to cook ÷ (1 − share lost to trim)portions = what you have ÷ amount per person, rounded downWhy the trim is divided out
Trim is a share of what you buy, not of what you serve. Removing 25% of 5,133 g leaves 3,850 g, so 5,133 g is the right purchase. The mistake of adding 25% of 3,850 g instead is the same one people make removing sales tax from a price, and it always leaves you short.
With your numbers
- To buy = per person × people × (1 + extra) ÷ (1 − trim)
Quick reference
The amount per person is yours: no serving size is stored, because published figures disagree.
| Example | Result |
|---|---|
| 20 people at 175 g | To cook: 3.5 kg |
| 20 people, 10% extra | To cook: 3.85 kg |
| 20 people, 10% extra, 25% trim | To cook: 3.85 kg |
| 3 kg on hand at 175 g | Portions you can serve: 17 |
| 12 people at 1 cup of soup | To cook: 3.3 qt |
| 50 people at 6 oz, 30% bone | To cook: 20.63 lb |
Common questions about the Serving Size Calculator
- How much food per person should I allow?
- The page does not suggest a figure, because there is no single right one: it depends on the dish, what else is served, the time of day and the people eating. Use your recipe’s serving size, or weigh what a plate of it holds, and enter that.
- How do I allow for bones or trimming?
- Divide by the share that is left, do not multiply by the share that is lost. If 25% of a cut is bone and trim, what you eat is 75% of what you buy, so you need 3,850 g ÷ 0.75 = 5,133 g. Multiplying by 1.25 gives 4,813 g instead, 320 g short, which is a plate or two for a party.
- Why are portions rounded down?
- Because you cannot serve part of a portion. 3 kg at 175 g each is 17.14 portions, and the honest answer is 17. Most counts on this site round up, since you cannot buy part of a bag; here the rounding runs the other way.
- How is the cost per serving worked out?
- The total cost is divided by the servings you cook for, which is the number of people plus the extra for seconds. Trim is paid for but not served, so it raises the cost per serving.