This is how to determine calories in beer...

BEER CALORIE CHEATSHEET

fl. oz. *ABV(Alcohol By Volume) = potency / 60 = beers * 150 C = Estimated Calories.

With an average beer (indicated as beers below) at 5% in a 12 fl oz size coming out to about 150 calories on average, applying this formula to a standard brew (e.g. a Budweiser) works like this:

A 12 fl. oz. Budweiser * 5% ABV = 60 (potency)/ 60 = 1 beers * 150 Calories = 150 estimated Calories

Based very much on the idea that we know grams of alcohol are specifically increasing along with ABV, even though grams of carbs/fat/protein if any may be staying the same or becoming less per volume in order to make room for the alcohol grams, we can gather that calories are increasing along with ABV. You might not have known but calories per gram of alcohol are similar to fat grams, and here’s some nutritional science on that:

Calculating calories per gram of carbohydrates, fat or protein is easy. All you need to remember is that:

* 1 gram of carbohydrate = 4 calories
* 1 gram of protein = 4 calories
* 1 gram of fat = 9 calories
* 1 gram of alcohol = 7 calories
Address : http://yourtotalhealth.ivillage.com/diet-fitness/how-count-calories-per-gram.html

So with this in mind, we can derive a scale with which we can fairly accurately guess at the caloric content of beers according to the ABV rating, which is usually able to be determined via thebottle or web site.

12*5% = 60 / 60 = 1.0 * 150 = 150C (e.g. Budweiser American Ale)
12*6% = 72 / 60 = 1.2 * 150 = 180C (e.g. half a Rogue Shakespeare Stout)
12*7% = 84 / 60 = 1.4 * 150 = 210C (e.g. Sierra Nevada Torpedo)
12*8% = 96 / 60 = 1.6 * 150 = 240C (e.g. Russian River Pliny the Elder)
12*9% = 108 / 60 = 1.8 * 150 = 270C (e.g. half a Brooklyn’s Local 2)
12*10% = 120 / 60 = 2.0 * 150 = 300C (e.g. half a Brooklyn Black Ops)
12*11% = 132 / 60 = 2.2 * 150 = 330C (e.g. Rochefort Trappistes 10 Ale)
12*12% = 144 / 60 = 2.4 * 150 = 360C (e.g. Dogfish Head Santo Palo Marron)
12*13% = 156 / 60 = 2.6 * 150 = 390C
12*14% = 168 / 60 = 2.8 * 150 = 410C
12*15% = 180 / 60 = 3.0 * 150 = 440C
12*16% = 192 / 60 = 3.2 * 150 = 470C
12*17% = 210 / 60 = 3.4 * 150 = 500C (e.g. Mikkeller 黑)
12*18% = 222 / 60 = 3.6 * 150 = 530C (e.g. half a Dogfish Head World Wide Stout)
12*19% = 234/ 60 = 3.8 * 150 = 560C
12*20% = 246 / 60 = 4.0 * 150 = 590C
12*21% = 258/ 60 = 4.2 * 150 = 620C (e.g. Dogfish Head’s 120 Minute IPA)

Of course if you are drinking from pint classes, that 12 turns into a 16, etc...

With this, we can deduct that a 12 fl oz Dogfish Head 120 Minute IPA (at a whopping 21% ABV) is a bit less than 2x our caloric rating for a 12 fl oz at 11% ABV (660C) or 12% ABV (720C). No matter, one bottle is about a third of a 2000 calorie daily diet.