top of page
  • Writer's pictureHeather Docherty, TWP

The Inaccuracy of Drink Calculators

Drink calculators can be wonderful tools to help you figure out how many servings of alcohol or non-alcoholic beverages you need for your wedding or event. They will never underestimate how much you'll need. Drink calculators are easy to use, but their simplicity often leads to gross overestimation. That means you can end up spending a lot more money than necessary and end up with too many leftover beverages.

So what do you do to get an accurate estimate? First, know your guests. Count up how many adults will drink alcohol, how many won't drink, and how many underage people are attending. After you have your drinking guest count, determine how many are likely to be average drinkers, light drinkers, or heavy drinkers. Include older guests or guests you're unsure about in your light drinkers count.

Multiply the number of hours your event will last by the number of average drinkers (1 drink/hour), heavy drinkers (2 drinks/hour), and light drinkers (0.5 drinks/hour). Most wedding receptions are 4-5 hours long. This formula does account for a cocktail hour, so if you aren't having a cocktail hour reduce your number of event hours by one. Here's an example for a 5-hour event without a cocktail hour:

75 light drinkers x 4 event hours = 300 drinks x 0.5 = 150 drinks

50 average drinkers x 4 event hours = 200 drinks x 1 = 200 drinks

25 heavy drinkers x 4 event hours = 100 drinks x 2= 200 drinks

TOTAL = 550 alcohol servings

Finally, know what types of alcoholic beverages your guests will want. Do they prefer liquor or do they prefer beer or wine? Offer a minimum of two choices each of liquor, beer, and wine but no more than five options. If you're only offering beer and/or wine, consider giving your guests at least three options of each. Estimate how many or what percentage of your guests will prefer each type of alcohol. Here's an example of how to do the math:

50% of drinkers prefer beer, 15% prefer wine, and 35% prefer liquor:

550 alcohol servings x 0.5 = 275 servings of beer (12 24-packs)

550 alcohol servings x 0.15 = 83 servings of wine (9oz/serving=29 bottles 750L size)

550 alcohol servings x 0.35 = 193 servings of liquor (193oz=8 bottles 750L size)

Don't forget about non-alcoholic drink options! These calculations are easier since you can use your total guest count and total number of event hours. Multiply the number of guests by the number of hours your event will last. This will tell you how many total drinks you'll need. Subtract the number of alcohol servings from the total non-alcoholic servings.

250 guests x 5 hours = 1250 servings

1250 servings - 550 alcoholic drinks = 700 non-alcoholic drinks

Next, you'll figure out how much of each beverage option you'll need. Always include water (tap or bottled) as one drink option. Are your guests mostly sweet tea fans or do they prefer unsweet? If you have lots of kids attending, consider lemonade or sodas too. Divide that by the number of non-alcoholic drink options you will offer. Here's an example with three drink options: water, unsweet tea (with optional sweetener) and lemonade.

700 non-alcoholic drinks / 3 drink options = 233.3333

234 bottles of water (5-6 cases)

233 8oz servings of unsweet tea (15 gallons)

233 8oz servings of lemonade (15 gallons)

Does this still sound like a lot of beverages? That's because it is! In over six years of hosting and coordinating events, we've noticed that one-third to half of the guests leave soon after food and desserts have been served. That is more true of weddings than other types of events. Once you have your calculations as we've shown above, reduce all your totals by 1/3 to 1/2. That will give you much more accurate and realistic numbers.

Here are the totals we figured up and the recommended amount to buy for a wedding with 250 guests:

Calculated Totals

Amount to Buy

12 cases of beer (24 packs)

8 cases of beer (24 packs)

29 bottles of wine (750L size)

20 bottles of wine (750L size)

8 bottles of liquor (750L size)

5-6 bottles of liquor (750L size)

5-6 cases of water (40-48 bottles/case)

4-5 cases of water (40-48 bottles/case)

15 gallons of unsweet tea

10 gallons of unsweet tea

15 gallons of lemonade

10 gallons of lemonade

You can still buy a little more than that if you absolutely want to be sure you don't run out. If you don't want to deal with all the math, consider hiring a professional bar service or a wedding planner who will help you with all of it.

Recent Posts

See All


bottom of page