What this calculator does
Find out how big a turkey to buy, so everyone gets a good plate and you get the leftovers you want. Most of a whole turkey's weight is bone, skin and juices. That's why a bird that looks huge in the store feeds fewer people than you might expect. A good starting point is about 1 pound of whole turkey for each adult.
This calculator starts from that rule and adjusts it for your table. Children count as half a portion. You can say whether your crowd eats lightly or heartily, and how many leftovers you'd like. It also works for a bone-in or boneless turkey breast. For a whole bird, it adds the thawing and roasting time, so you can plan the days ahead.
Where it's used
Why this math matters outside the classroom:
- Holiday shopping. A host with 12 adults and no leftovers plan buys 12 lb of whole turkey at about 1 lb per person.
- Leftover planning. Wanting sandwiches the next day, a family of 10 adults buys 15 lb, using 1.5 lb per person.
- Office potluck. An organizer feeding 8 people with a boneless roast buys about 4 lb, at 1/2 lb per person.
- Kids at the table. With 6 adults and 4 children, a host counts 6 + 4 × 0.5 = 8 portions before scaling up.
- Classroom rates. Students practice unit rates by scaling 1.25 lb per portion to 9 portions, which is 11.25 lb.
Grade level and standards: Grade 6; Common Core State Standards for Mathematics 6.RP.A.3.b. © Copyright 2010. National Governors Association Center for Best Practices and Council of Chief State School Officers. All rights reserved.
How to use it
- Enter the number of adults and teens, then the number of young children.
- Pick how much your guests tend to eat and how many leftovers you want.
- Choose a whole turkey or a breast.
- Shop for a bird close to the size shown. A pound or so either way is fine.
What the inputs mean
- Young children
- Count young children who eat a small plate. Teens usually eat like adults, so count them with the adults.
- Appetite
- Light eaters take 80% of the usual amount, and hearty eaters take 125%. Pick hearty if there are lots of other dishes missing, or if your family loves turkey.
- Leftovers wanted
- Some adds a quarter more. Plenty adds half again, which is enough for sandwiches the next day.
- What you're buying
- A breast has less bone than a whole bird, so you need fewer pounds per person. A boneless roast has no bone at all.
Formula and method
portions = adults + 0.5 × children pounds per portion = base × appetite × leftovers turkey to buy = portions × pounds per portion, rounded up to a whole pound base: whole turkey 1 lb, bone-in breast 0.75 lb, boneless breast 0.5 lb
The base is the raw weight per adult for one meal with no leftovers. It's the amount many food-safety and cooking guides suggest: about 1 lb of whole bird, 3/4 lb of bone-in breast, or 1/2 lb of boneless breast.
Appetite is 0.8 for light eaters, 1 for average and 1.25 for hearty. Leftovers are 1 for none, 1.25 for some and 1.5 for plenty. The calculator multiplies these together, then rounds the total up so you don't run short.
Worked example
You're hosting 8 adults and 2 young children. They have average appetites, and you'd like some leftovers. You want a whole turkey.
- Portions: 8 + 2 × 0.5 = 9.
- Pounds per portion: 1 lb × 1 × 1.25 = 1.25 lb.
- Total: 9 × 1.25 = 11.25 lb, rounded up to 12 lb.
- A 12 lb bird roasts in about 2 h 35 min to 3 h at 325 °F unstuffed. It needs about 2.4 to 3 days to thaw in the fridge.
Result: Buy a whole turkey of about 12 lb (about 5.4 kg).
Understanding the result
Treat the answer as a target, not an exact order. Turkeys come in whatever size the farm raised, so pick the nearest one you can find. Going a pound or two over just means more leftovers.
If the answer is over 30 lb, two smaller birds are easier. They fit in a home oven, thaw faster and cook more evenly. If it's under 4 lb, a turkey breast is usually a better buy than a tiny whole bird.
Assumptions and limitations
- Weights are raw weights, as printed on the label, before cooking.
- Turkey is the main dish, served with the usual sides.
- Young children eat about half an adult portion.
- The appetite and leftover settings are rules of thumb. They aren't measured standards, so adjust them to your own family.
- The times shown are for an unstuffed whole bird at 325 °F. A stuffed bird takes longer. The turkey cooking time calculator covers that.
- Time is only a guide. A turkey is safe to eat only when a food thermometer reads 165 °F (74 °C) in the thickest part of the thigh and breast.
Frequently asked questions
How much turkey per person should I buy?
Plan on about 1 lb of whole turkey per adult for one meal. Plan on about 1.5 lb if you want leftovers. For a bone-in breast, allow about 3/4 lb per person. For a boneless breast or roast, allow about 1/2 lb.
Why do I need so many pounds per person?
Much of a whole turkey is bone, skin and fat, and it loses juices as it cooks. A 1 lb share of raw bird gives a plate of meat that most adults find generous.
How early should I buy a frozen turkey?
Buy it early enough to thaw it in the fridge. That takes about 1 day for every 4 to 5 lb. A 12 lb bird needs about 3 days, so plan a few extra days for shopping. Never thaw it on the counter.
Is one big turkey or two small ones better?
For a very large crowd, two small birds are often easier. They thaw faster, roast more evenly, and you can cook them on different days or in different ovens. One big bird looks grand, but it takes longer at every step.
How this calculator is checked
Method: USDA consumer guidance on turkey per person (about 1 lb whole bird, 3/4 lb bone-in breast, 1/2 lb boneless breast or roast). Appetite (0.8, 1, 1.25) and leftover (1, 1.25, 1.5) multipliers are planning rules of thumb; 1.5 lb per person with leftovers matches the common host rule. Thawing and roasting times come from src/lib/food/turkey.ts, shared with turkey-cooking-time. The calculation is covered by automated tests with known reference values and edge cases. Last updated 2026-10-25. Found a problem? Tell us.
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