How much beer do I need for 15 guests?

You need 4 cases of beer for 15 guests at a graduation party. This provides 73 total servings with a 15% buffer to ensure you don't run out.

How much beer per person for a graduation party?

Plan for 4.9 servings of beer per person at a graduation party. This accounts for the fact that not everyone drinks alcohol and consumption naturally slows as the event progresses.

How many servings are in a case of beer?

One case of beer contains 24 servings. For 15 guests, you'll need 4 cases to provide 73 total servings.

What percentage of guests will drink beer at a graduation party?

At a graduation party with 15 guests, approximately 12 guests (80%) will actively drink. Our formula accounts for this when calculating the 4 cases you need.

Should I buy extra beer as a buffer?

Yes! Our calculation of 4 cases already includes a 15% buffer (0 extra cases). This ensures you won't run out even if some guests drink more than average. It's always better to have leftovers than to run short.

How long will 4 cases of beer last for 15 guests?

4 cases of beer will last approximately 4 hours for 15 guests at a graduation party. This calculation factors in the natural slowdown of consumption as the event progresses.

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How Much Beer for a 15 Guest Graduation Party?

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cases of beer

For a 15-guest graduation party lasting 4 hours

15% buffer included

Total servings

4.9

Per person

Buffer cases

How We Calculated This

Our bartender-tested formula, step by step

Estimate actual drinkers

15 guests × 80% drinking rate

= 12 drinkers

At small events, about 80% of guests typically drink alcohol.

Calculate base consumption

12 drinkers × 1.5 drinks/hour × 4 hours

= 72 base drinks

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

Apply consumption decay

Adjusted for drinking slowdown over time (decay factor: 3.25)

= 59 adjusted drinks

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

Apply graduation party modifier

× 1.25 (+25% for beer)

= 73 beer servings needed

Graduation Partys typically consume 25% more beer than average.

Convert to cases

73 servings ÷ 24 servings per case

= 3 cases (raw)

Each case of beer provides 24 servings.

Add 15% buffer & round up

3 × 1.15 = 3.4, rounded up

= 4 cases

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: Beer by Guest Count

Guests	Beer Needed	Total Servings
25 guests	7 cases	122 servings
50 guests	14 cases	243 servings
75 guests	20 cases	365 servings
100 guests	27 cases	487 servings
150 guests	40 cases	730 servings
200 guests	54 cases	973 servings

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

Your Shopping List

Everything you need, plus essentials you might forget

🍺

Beer

The main event

cases

Don't forget these

Ice (Keep those beers cold!)

48 lbs
Coolers (2 cases per cooler)

2 coolers
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Pro Tips for Your Graduation Party

Insider advice from experienced bartenders

💡

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

⏰

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

🎯

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

🧊

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

✨

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

🛒 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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