Alcohol Calculator for Event Planning

Enter your expected guest count and how many hours you'll be serving alcohol. Adjust the beer/wine/liquor split if you know your crowd skews toward one category — for example, a wedding crowd often drinks more wine, while a casual backyard party often skews toward beer. The calculator converts total estimated drinks into bottles of wine, cases of beer, and bottles of liquor so you know roughly what to buy or ask your bartending service to source.

Event planners have used this rule for decades because it holds up reasonably well across most private events: guests don't drink continuously for the entire event, but averaged across arrivals, toasts, meals, and slower stretches, one drink per hour per guest tends to match real consumption closely enough to plan around.

It's a planning estimate, not a guarantee — some guests will drink less, a few will drink more, and weather, event type, and time of day all nudge the number slightly. That's exactly why buying a little extra headroom (rather than the bare calculated minimum) is the safer move covered below.

Unopened wine and liquor are usually returnable at many Colorado liquor stores if you don't open them, so there's little downside to rounding up. Beer is the exception — buy closer to your actual estimate since unopened beer is less commonly returnable and doesn't keep as well long-term.

Plan for non-drinkers, designated drivers, and guests who simply want something else late in the night. A rough guide is one non-alcoholic drink (soda, mocktail, sparkling water) per guest for the full event length, in addition to your alcohol total.