How many drinks do you need to serve at a party? There are lots of online calculators that can help you figure it out, but we especially like the one at Real Simple. Not only does it include cheese and hors d'oeuvres in addition to beverages, but it lets you account for gatherings with adults and kids.

Real Simple's Party Food and Beverage Calculator is limited in that it only includes advice for parties of 6, 12, or 24 guests, but it's a great starting point. Most calculators we've seen only address beer, wine, liquor, and maybe mixers. This one includes all of those plus ice, soda (cola and ginger ale), juice, and even juice boxes if kids are involved. On the food side, it advises on quantities of cheese and hors d'oeuvres.
How do you calculate how much food and drink to serve at a party?
→ Try it: Party Food and Beverage Calculator at Real Simple
Related: Mixer Math: How To Calculate Alcohol Needs for a Party
(Images: Sara Kate Gillingham-Ryan; Real Simple)
Martha Concrete Lam...

I always estimate a reasonable amount, prepare that, and then freak out two hours before that it's not enough food and speed to the grocery for more. I don't think all the calculators in the world will stop my pre-party panic.
I usually keep some sort of ultra-simple "back-up" drink supplies on hand. My last party, for example, I got some grapefruit soda and a bottle of tequila for palomas in case we ran out of supplies for the main drinks.
um, i wouldn't say that it's accurate. for example, for 12 people it suggests:
Wine (Red, White, and Sparkling): 7 to 8 bottles total
Beer: 3 six-packs
Basic Liquor: 2 bottles each of Vodka, Gin, and Rum
Optional Liquor: 1 bottle each of Bourbon and Blended Scotch
Juice and Soda: 1-2 bottles each of Cola, Ginger Ale, Cranberry Juice, and Orange Juice
Seltzer and Tonic: 3 bottles of each
Ice: 12 pounds total
Garnishes: 3 lemons, 3 limes
Cheese: 6 pounds total
Hors d'oeuvres: 48 to 72 pieces
really, 6 lb of cheese? and that's a LOT of liquor for 12 people - 6 bottles (plus wine, and beer)!
i'd rather do my own calculations based on the crowd...
this is a terrible calculator!! I would have expected AT to check before posting. I tried for 12 people which includes children as well...you don;t need 7 to 8 bottles of wine plus beer....