The amount of carbohydrates in a beer will vary depending on what brand of beer it is. For example, one 12 ounce Bud Light beer contains 6.6 grams of carbs. A lower Carbohydrate choice that Budweiser also now offers is "Budweiser Select". A 12 ounce bottle of Bud Select only has 3.1 grams of carbohydrates. You can generally find the grams of carbs contained in other brands of beer listed on the can or bottle itself and the amount will be for a single serving, or per/each.