How this calculator works

The math behind the bar is simpler than it looks. Caterers and bartenders plan on two drinks per guest for the first hour, then one drink per guest for each hour after that — cocktail hour is always the thirstiest part of the night. We multiply that by your crowd’s drinking style (a brunch wedding with grandparents drinks very differently from a Saturday-night dance party), then split the total across beer, wine and spirits using your bar mix.

Bottle math: a 750 ml bottle of wine pours 5 glasses, a 750 ml bottle of spirits makes about 16 cocktails at a 1.5 oz pour, and a bottle of sparkling fills 6 toast flutes. Beer is one serving per bottle or can, rounded up to full cases so you’re never caught short.

Tips from wedding bartenders

• Buy 10–15% more than the estimate if your venue or store accepts returns of unopened bottles — most do. It’s free insurance.
• Chill in stages. You’ll never fit it all in the fridge; plan on roughly 1.5 lb of ice per guest for chilling and serving (we include it in the list).
• Limit the spirits list. Two signature cocktails plus vodka, whiskey and tequila covers 95% of requests and costs far less than a full bar.
• Don’t forget the non-drinkers. Plan one soft drink or sparkling water per guest per hour — included when mixers are checked.
• Check your venue’s corkage and licensing rules before buying anything. Some venues require a licensed bartender to serve alcohol you supply.

Estimates are a planning guide, not a guarantee — always follow your venue’s rules and local laws, and never serve guests under the legal drinking age.