Party Drink Calculator

How much alcohol do you need for a party?

Start with the formula guests × hours × drinks-per-hour. Most party guides settle on 1.5 drinks per guest per hour as the number that keeps a bar stocked without creating a trough of half-finished cups. Twenty guests over four hours: 20 × 4 × 1.5 = 120 drinks. That single total is the anchor for every purchase you make — you just have to divide it up by category.

A 50% beer, 30% wine, 20% liquor split handles most crowds well. Take the 120-drink example: 60 beers (about 3 cases of 24), 36 glasses of wine (about 8 bottles), and 24 shots (about 2 bottles of liquor). The split is a starting point, not a law. A brunch party leans toward mimosas and spritzers; a poker night is mostly beer. Change the percentages, keep the total.

The other variable is duration. A two-hour party at 1.5 drinks/hour needs 3 drinks per guest; a six-hour barbecue needs 9. That is why the table above is built around a four-hour baseline — scale it up or down by changing the hours in the calculator. And when you are budgeting, remember that the money a regular habit eats adds up the same way: the cost calculator turns small daily purchases into a yearly total in seconds.

Matching the mix to the party

The 50/30/20 default works for a generic barbecue, but party type is the real driver of the mix. A brunch runs on mimosas and light beer, a game night is beer-dominant, a dinner party skews to wine, and a cocktail party lives on liquor. Start from these splits and adjust to taste:

Percentages are share-of-drinks; the total drink count stays fixed when you change the split.

Changing the split does not change the total — the calculator keeps your drink count fixed and simply re-buckets it. That is the right order of operations: decide the total from guests × hours × rate, then decide the mix, then convert to cases and bottles.

Ice, cups, and mixers: the forgotten 20%

The drink math covers alcohol; the shopping list needs everything around it. Budget roughly one pound of ice per guest for a four-hour party, one cup per drink (reusable cups slash this), and mixers at about 1.5 ounces per liquor drink — tonic for gin, soda for whiskey, juice for vodka. For every bottle of liquor, plan roughly 1.5–2 bottles of mixer. A 120-drink party at 50/30/20 needs about 24 liquor drinks, or roughly 36 ounces of mixer.

Garnishes are cheap but embarrassing to run out of: lemons and limes at roughly one per three guests, olives if you are offering martinis, and a sparkling-water option. Keep a non-alcoholic zone stocked so designated drivers and light drinkers are covered without tapping the alcohol supply.

A worked example: 30 guests, 3 hours

Take 30 guests for a three-hour barbecue at the standard 1.5 drinks per hour: 30 × 3 × 1.5 = 135 drinks. At a beer-heavy 60/25/15 split, that is 81 beers (about 3.5 cases of 24, so buy 4), 34 glasses of wine (about 7 bottles), and 20 shots (about 2 bottles of liquor). Add a 10–15% beer and liquor buffer and the shopping list lands at roughly 5 cases, 7 bottles of wine, and 2–3 bottles of liquor.

Bulk stores and warehouse clubs sell sealed cases at the best per-unit price, and most take back unopened cases after the party — buy the buffer there. Liquor stores are the better move for wine when you want selection or buy-back on bottles. Whatever the occasion, plan the total first, then let the calculator (or the table above) do the conversion, and the bar will hold up until the last guest leaves.

The same alcohol math scales to bigger events. The wedding alcohol calculator adapts the formula to receptions with ratio and buy-back advice, and the keg calculator sizes the beer portion by the barrel for larger crowds.