If you're watching carbs — keto, low-carb, or just cutting back — bourbon is one of the easiest drinks to fit in. The short answer: straight bourbon has zero carbs and zero sugar. The catch is never the whiskey; it's what you pour it into.
Why bourbon has no carbs
It comes down to distillation. Bourbon starts as a sugary mash of grain — at least 51% corn — and fermentation converts nearly all of that sugar into alcohol. Then distillation separates alcohol and water vapor from everything else: sugars, proteins, and carbohydrates are too heavy to carry over and get left behind in the still. What ends up in the bottle is essentially alcohol and water. No carbs make it across, because carbs can't ride the vapor. Aging in oak adds color and flavor, not sugar.
This is true of every unflavored distilled spirit — bourbon, rye, Scotch, vodka, gin, tequila. Flavored whiskeys and liqueurs are the exception, because sugar is added after distillation.
Calories, though, are a different question
Zero carbs doesn't mean zero calories. Alcohol itself carries about 7 calories per gram, so a standard 1.5 oz pour of 80-proof bourbon runs roughly 97 calories — all from the alcohol, none from carbs. Higher proof means more calories: a barrel-proof bourbon at 120 proof pushes closer to 125–140 calories per pour. Compare that to beer, where a single 12 oz can carries 12–13 grams of carbs and 150+ calories.
What actually adds the carbs
- Neat or on the rocks: 0 g carbs.
- Bourbon and diet soda / soda water: still ~0 g carbs.
- Bourbon and cola: about 39 g carbs come from a 12 oz regular cola — all from the mixer.
- Whiskey sour, Old Fashioned, Manhattan: 5–20+ g, depending on simple syrup, sweet vermouth, or juice.
The whiskey is the "free" part of the drink. If you're keeping carbs down, drink it neat, over ice, or with soda water and a citrus twist.
A realistic note for low-carb and keto drinkers
Because there's no carbohydrate buffer in your system, alcohol tends to hit faster and hangovers can feel worse on a strict low-carb diet — so pace yourself and hydrate. Alcohol calories also aren't "free" calories; the liver prioritizes clearing alcohol over burning fat while it's processing a drink. Bourbon fits a low-carb lifestyle better than almost any other drink, but moderation still matters.
Quick answers
How many carbs in a shot of bourbon? Zero. Is bourbon keto-friendly? Yes, taken neat or with a zero-carb mixer. Does higher proof mean more carbs? No — more calories, but still zero carbs. What about flavored bourbon? Those can contain added sugar; check the label.
Curious how the spirit gets that clean profile in the first place? Read how bourbon is made, or see whether bourbon is gluten-free (short version: yes).
