Every time you've stepped foot into a liquor store or bar, you’ve probably been overwhelmed with all of the choices: light beer, stouts, IPAs, liquors, liqueurs, and don’t even get us started on the amount of wine that’s out there. Choosing the right drink is a challenge, and what we have to say might make it even trickier.

What's One Drink?

While you're trying to figure out what you feel like drinking, you might want to take into consideration how hungover you want to be tomorrow. Within the large variety of alcoholic beverages, there are also huge variances in alcohol by volume (ABV) percentages in each drink. This means that ‘one drink’ isn’t as simple as one can of beer, one glass of wine, or one cocktail on the rocks. So how’s a person supposed to keep their "I'm only having three drinks tonight" promise?

Men can consume up to two drinks per day and women can have one drink per day without any negative health implications, according to the government's 2015-2020 . Sounds easy enough, but these recommendations pose the question—what the heck is one drink?

“It’s complicated because not all alcoholic drinks are created equal,” says Taylor C. Wallace, Ph.D., C.F.S., and researcher for .

To make it even more confusing, one alcoholic drink-equivalent is described as containing 14 grams (0.6 fluid ounces) of pure alcohol. That’s equal to:

  • 12 ounces of regular beer, with 5% alcohol
  • 5 ounces of wine, with 12% alcohol
  • 1.5 ounces of 80 proof distilled spirits, with 40% alcohol

But not all drinks adhere to these standard numbers. Craft beers have more than 5% alcohol and wines can range from 5 to 15%. And spirits are all over the place. “If you have a 12-ounce beer with 10% alcohol by volume (ABV), you’re actually really having two drinks,” Wallace says. “If that’s not complicated enough, most beers come in standard sizes (a 12-ounce can or bottle), but imagine trying to calculate drink-equivalents for a vodka soda at a restaurant or bar,” he adds.

How Can You Tell How Many Drinks You're Having?

There’s a simple formula (because we know you miss old-school algebra):

  • Drink equivalents = ((ABV% x 100) x fluid ounces consumed) / 0.6
  • Or if this is making your brain hurt, try this handy if you really want to nerd out know.

We don’t expect you to whip out your calculator every time you order a drink. That’s a surefire way to repel everyone at the bar. Instead, here’s the math on some of the most common drinks you're ordering (skip to the bottom of the list to learn what the numbers really mean).

Budweiser

  • Your standard 12-ounce bottle of Bud has 5% ABV.
  • Drink equivalent per 12 ounces: 1

Bud Light

  • The lighter 12-ounce bevvie only has 4.2% ABV.
  • Drink equivalent per 12 ounces: 0.84

Goose Island Bourbon County Brand Coffee Stout 2016

  • This award-winning stout is only sold in large quantities, and it’s got a whopping 13.4% ABV.
  • Drink equivalent per 12 ounces: 2.68

Brooklyn East IPA

  • The alcohol for traditional IPA’s vary per brand, but this New York City variety has 6.9% ABV.
  • Drink equivalent per 12 ounces: 1.38

Ommegang Pale Sour

  • Sour beers are on trend, and many of them have more alcohol than the traditional bottled beer. This one is 6.9% ABV.
  • Drink equivalent per 12 ounces: 1.38

Bulleit Bourbon

  • Not all hard liquors have the same amount of alcohol. This variety of bourbon is 45% ABV (90 proof).
  • Drink equivalent per 1.5 ounces: 1.12

Grey Goose Vodka

  • Most standard vodkas are 40% ABV, meaning they are one of the rare exceptions that fits into the perfect 1 drink equivalent.
  • Drink equivalent per 1.5 ounces: 1

Bailey’s Irish Cream

  • Anyone who has ever tried this sweet after-dinner drink can probably tell you that it’s lower on the alcohol scale, with 17% ABV.
  • Drink equivalent per 1.5 ounces: 0.43

Cupcake Moscato

  • This sweet wine is similar to beer, with a 5.5% ABV.
  • Drink equivalent per 5 ounces: 0.45

Robert Mondavi Cabernet Sauvignon

  • This classic red wine has 15% ABV.
  • Drink equivalent per 5 ounces: 1.25

Edna Valley Vineyard Chardonnay

  • Your buttery Chardonnay contains, on average, about 14.5% ABV.
  • Drink equivalent per 5 ounces: 1.2

WTF do these numbers mean, though?

The bottom line is that the ABV isn’t nearly as important as the drink-equivalent. The latter lets you know exactly how many ‘drinks’ you are taking down in that one bottle of beer, glass of wine, or cocktail. If the drink equivalent is more than 1, that beverage has more than the acceptable amount of alcohol for a woman and two of those drinks is more than a man should have in a day.

Bottoms Up

Let’s be real. Friday night cocktails are going to happen. What’s not going to happen is you measuring up drink equivalents before you order. But since alcoholic bevs don’t come with a nutrition facts panel or drink equivalent chart, you might as well be somewhat aware of these numbers. That way, when you have a beer with 12% ABV and wake up with a monster hangover the next day, at least you’ll know why. And because one drink can “raise your good blood cholesterol, but over-consumption can have detrimental effects,” Wallace says, it’s important to drink responsibly. If you’ve got any underlying health problems, check with a doctor or registered dietitian before doing any keg stands.

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