When determining the ideal size of a turkey for your holiday gathering, several factors come into play, and there is indeed a helpful guideline to follow. Generally, the rule of thumb is to allocate about 1 to 1.5 pounds of turkey per person. This range accounts for both the actual meat consumption and some allowance for bones and shrinkage during cooking. For example, if you expect 8 guests, a turkey weighing between 8 to 12 pounds would usually suffice.

You absolutely should factor in the number of guests who will be partaking in the meal, as this is the primary variable in sizing your bird. If you want to ensure there are leftovers for sandwiches, salads, or next-day reheats—a common and delicious bonus—consider skewing towards the higher end of the range or slightly beyond. Leftovers are often a welcomed perk, but if your gathering is smaller or if you anticipate lighter eaters, a more conservative estimate reduces waste and storage needs.

The size of your event indeed changes the dynamic. For a small, intimate group, a smaller bird or even a spatchcocked turkey might be preferable, reducing cooking time and minimizing leftovers. In contrast, a large family reunion often calls for multiple birds or a very large one to accommodate diverse appetites and allow everyone to have seconds or thirds.

Regarding a brined turkey, the weight before and after brining can differ slightly, particularly due to water absorption—a factor that might add up to a pound or two. However, the increase is usually minimal and shouldn’t significantly affect your planning. Just keep in mind that a brined turkey tends to retain more moisture, so cooking times might vary slightly, but the size calculation stays pretty much the same.

Your choice of cooking method—roasting, smoking, deep-frying—can influence how the bird shrinks during cooking. Frying, for instance, might result in less moisture loss compared to roasting. While these differences don’t drastically affect how much turkey you need to buy, they could impact cooking time and texture, which are also worth considering.

In the end, prioritize the number of guests and their expected appetites, your desire for leftovers, and the practicality of cooking and storing large birds or multiple smaller ones. It’s often wiser to lean slightly generous, especially during holidays when good food and shared moments matter most. This way, your turkey will delight and satisfy all gathered without undue stress or shortage.