How the turkey calculator works
It does three things. First it sizes the bird: about 1 pound of whole turkey per guest covers the meal, since bones make up a large share of the weight, and 1 1/2 to 2 pounds leaves leftovers. Then it estimates thawing time using the USDA's rules for the refrigerator and cold-water methods. Finally it looks up the USDA's roasting time range for a turkey of that weight in a 325 °F oven.
The formula
boneless breast = guests × 0.5 · 0.75 · 1 lb
fridge thawing ≈ weight ÷ 5 to weight ÷ 4 days (24 h per 4–5 lb)
cold-water thawing ≈ weight × 30 minutes
roasting time = USDA range for the weight class, at 325 °F
Example: 10 guests with leftovers
| Step | Result |
|---|---|
| Size: 10 × 1.5 lb | 15 lb |
| Fridge thaw: 15 ÷ 5 to 15 ÷ 4 = 3 to 3.75, rounded up to the half day | 3–4 days |
| Cold water: 15 × 30 min | 7 h 30 min |
| Roasting, unstuffed (14–18 lb row) | 3 h 45 min – 4 h 15 min |
| Done at | 165 °F, then rest 20 min |
USDA roasting times at 325 °F
| Weight | Unstuffed | Stuffed |
|---|---|---|
| 4 to 8 lb (breast) | 1 1/2 to 3 1/4 hours | Not listed |
| 8 to 12 lb | 2 3/4 to 3 hours | 3 to 3 1/2 hours |
| 12 to 14 lb | 3 to 3 3/4 hours | 3 1/2 to 4 hours |
| 14 to 18 lb | 3 3/4 to 4 1/4 hours | 4 to 4 1/4 hours |
| 18 to 20 lb | 4 1/4 to 4 1/2 hours | 4 1/4 to 4 3/4 hours |
| 20 to 24 lb | 4 1/2 to 5 hours | 4 3/4 to 5 1/4 hours |
Source: USDA Food Safety and Inspection Service roasting guidelines for a fully thawed turkey in a 325 °F oven. Oven accuracy, how cold the bird starts, the pan and how often you open the door all shift the actual time, which is why the thermometer, not the clock, decides when it's done.
Turkey tips
- Count back from dinner. Add the thaw days, plus a day of slack, and move the turkey to the fridge that morning.
- Check three spots. 165 °F in the innermost thigh, innermost wing and thickest part of the breast.
- Don't forget the giblets. Pull the neck and giblet bag out of both cavities before roasting.
- Let it rest. 20 minutes before carving keeps the juices in the meat and gives you time to make gravy.
- Bigger party? Two smaller turkeys cook faster and more evenly than one 24 pound giant.
Frequently asked questions
How much turkey do I need per person?
Plan on about 1 pound of whole turkey per person, or 1 1/2 pounds if you want leftovers. The bones and carcass make up a good part of the weight, so a 15 pound bird yields far less than 15 pounds of meat. For a boneless turkey breast, about 1/2 pound per person is enough, or 3/4 pound for leftovers.
How long does it take to thaw a turkey in the fridge?
The USDA says to allow about 24 hours for every 4 to 5 pounds in a refrigerator at 40 °F or below. A 15 pound turkey needs about 3 to 4 days. A thawed turkey keeps another 1 to 2 days in the fridge before cooking.
How do I thaw a turkey quickly?
Use the cold-water method: keep the turkey in its leak-proof wrapping, submerge it in cold tap water, and change the water every 30 minutes. Allow about 30 minutes per pound, then cook it right away. Never thaw a turkey on the counter or in warm water.
How long do I cook a turkey at 325 °F?
For an unstuffed whole turkey, roughly 3 to 3 3/4 hours for 12 to 14 pounds, 3 3/4 to 4 1/4 hours for 14 to 18 pounds, and 4 1/2 to 5 hours for 20 to 24 pounds, per the USDA. Stuffed birds take a little longer. These are estimates; the turkey is done when a thermometer reads 165 °F.
What temperature is turkey done?
165 °F, measured with a food thermometer in the innermost part of the thigh, the innermost part of the wing, and the thickest part of the breast. If the bird is stuffed, the center of the stuffing must also reach 165 °F.
Can I cook a turkey from frozen?
Yes. The USDA says it's safe, but it takes about 50% longer than a thawed turkey, and you remove the giblet packet partway through with tongs once it loosens.
Rates and figures last checked October 2026.
This calculator gives estimates for planning. Check current rates and product labels before you buy, list or file.