Cooking for a group: enter the headcount and appetite level and get shopping quantities for the main protein, sides, bread and drinks.
Standard planning portions: about 8 oz (225 g) raw bone-in or 6 oz (170 g) raw boneless protein per person before cooking, roughly 1 cup of each side per person spread across the sides served, one bread roll each plus spares, and about two drinks in the first hour then one per hour.
Group portions follow caterer planning rules: protein is the anchor at roughly half a pound of raw boneless meat per person (more for bone-in cuts, since bone and cooking loss come out of it), sides total about 1 to 1.5 cups per person divided across however many sides are served, and bread and drinks scale close to headcount with a margin for the first hour. The appetite setting scales the whole plan — mixed-age and lunch groups eat noticeably less than a group expecting seconds.
How much meat per person should be bought? For boneless cuts, about 1/2 lb (225 g) raw per person gives roughly 6 oz cooked. For bone-in cuts buy about 3/4 to 1 lb per person, and for ribs 1 to 1.5 lb, because bone makes up much of the weight.
Why does the number of sides change each side's amount? People eat a similar total volume of sides however many there are. With two sides each is eaten in larger portions; with five, smaller portions of each add up to about the same total.