How Much Alcohol Do I Need for My Party? (Guest-Count Calculator + Formulas)

The number one reason people over-spend on their bar is guesswork. The number one reason people run out of alcohol at 9:30pm is also guesswork. Here's the math bartenders actually use.

The 1-drink-per-guest-per-hour rule

Assume each adult guest will drink one alcoholic beverage per hour for the length of your event. It's the industry baseline every mobile bartender in Western NY plans against. So 100 guests × 5 hours = 500 drinks total.

The split: 50 / 30 / 20

For a mixed crowd, split total drinks: 50% beer, 30% wine, 20% liquor. Adjust by 5–10% either direction if you know your guests skew one way.

For 100 guests, 5-hour reception (500 drinks)

• Beer (250 drinks) → 10 cases (24 pack) — mix domestic, craft and a light option
• Wine (150 drinks) → 30 bottles — split roughly 60% white/rosé, 40% red
• Liquor (100 drinks) → 5–6 handles (1.75L) across vodka, gin, whiskey, rum, tequila
• Champagne for toast → 1 bottle per 8 guests = 12–13 bottles

The mixer & garnish rundown

• Club soda & tonic — 1 liter per 20 guests
• Cola, diet cola, ginger ale — 2 liters per 25 guests each
• Cranberry, orange, pineapple juice — 1 gallon per 40 guests each
• Limes — 1 per 10 guests · Lemons — 1 per 15 guests
• Ice — 1.5 lbs per guest (yes, that much — half for drinks, half for chilling)

Adjust for your crowd

• Wedding, cocktail-forward — shift to 40% beer / 30% wine / 30% liquor
• Corporate holiday party — 55% beer / 30% wine / 15% liquor
• Bridal / baby shower — 20% beer / 50% wine / 15% champagne / 15% cocktails
• Bachelor/bachelorette — 40% beer / 15% wine / 45% liquor

Use our free alcohol calculator

We built a free interactive tool that runs these formulas for your exact guest count, event length and crowd type — and outputs a printable shopping list you can hand to a local Rochester, Buffalo or Syracuse liquor store.