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How Much Spirits for a 100 Guest Graduation Party?

You will need approx.

🥃
20
bottles of spirits

For a 100-guest graduation party lasting 4 hours

info 15% buffer included
290
Total servings
2.9
Per person
+2
Buffer bottles

How We Calculated This

Our bartender-tested formula, step by step

1

Estimate actual drinkers

100 guests × 70% drinking rate
= 70 drinkers

At large events, about 70% of guests typically drink alcohol.

2

Calculate base consumption

70 drinkers × 1.5 drinks/hour × 4 hours
= 420 base drinks

Industry standard is 1.5 drinks per person per hour for a 4-hour event.

3

Apply consumption decay

Adjusted for drinking slowdown over time (decay factor: 3.25)
= 341 adjusted drinks

People drink faster in the first hour and slow down as the event progresses.

4

Apply graduation party modifier

× 0.85 (-15% for spirits)
= 290 spirits servings needed

Graduation Partys typically consume 15% less spirits than average.

5

Convert to bottles

290 servings ÷ 17 servings per bottle
= 17.1 bottles (raw)

Each bottle of spirits provides 17 servings.

6

Add 15% buffer & round up

17.1 × 1.15 = 19.7, rounded up
= 20 bottles

Always round up and add a buffer. Running out is worse than having leftovers!

Why trust this formula?

Based on industry standards and refined by bartenders with 30+ years of experience. We factor in consumption decay (people drink less as events progress) and real-world drinking percentages.

📊 Quick Reference: Spirits by Guest Count

Guests Spirits Needed Total Servings
25 guests 5 bottles 73 servings
50 guests 10 bottles 145 servings
75 guests 15 bottles 218 servings
100 guests (you) 20 bottles 290 servings
150 guests 30 bottles 435 servings
200 guests 40 bottles 580 servings

* All calculations include a 15% buffer. Amounts for graduation party.

The Essentials

🥃 20 bottles Spirits
97 liters Mixers (soda, tonic, juice) (Variety is key)
140 lbs Ice (~2 lbs per person)
140 glasses Cocktail glasses (2 per drinker) Buy
37 pieces Garnishes (limes, lemons)

The Host's Secret

Editorial Curation

ATMOSPHERE

"Set up a visible '21+ only' bar area and a killer mocktail station so younger guests feel included."

Pro Tip #1
PREPARATION

"Parents of graduates drink about 30% less than the graduate's friends - plan your ratios accordingly."

Pro Tip #2
TIMING

"Keep champagne cold but corked until group photo time - pop bottles for the shot!"

Pro Tip #3
SERVICE

"Outdoor graduations in summer need extra cold drinks and 2x the ice you think you need."

Pro Tip #4
PRESENTATION

"Mix of generations means variety is key - have options for every age group."

Pro Tip #5
🛒

Buying Guide

Graduation parties typically skew toward beer and lighter drinks. Stock up on popular light beers and have a good selection of non-alcoholic options since many guests will be under 21. Sparkling cider is a great champagne alternative for toasts that includes everyone.

🎉

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