How Many Carbs Are in 1 Cup of Black Coffee?: The Surprising Truth

October 9, 2025 •

4 min read

According to the United States Department of Agriculture (USDA), a standard 8-ounce (240 mL) cup of brewed black coffee contains essentially zero carbohydrates. This makes the question of "how many carbs are in 1 cup of black coffee?" surprisingly simple to answer, but the nutritional landscape changes dramatically once additives are introduced.

Quick Summary

This article details the nutritional profile of black coffee, revealing its negligible carbohydrate content and suitability for low-carb and keto diets. It explores how various additions like milk, sugar, and syrups drastically increase the carb count and offers healthy, low-carb alternatives. The text also covers black coffee's health benefits beyond its minimal carb and calorie counts.

Key Points

Black Coffee is Carb-Free: Pure, brewed black coffee contains virtually zero carbohydrates, calories, and fat, making it an ideal drink for low-carb and keto diets.
Additions Add Carbs: The high carbohydrate content often associated with coffee comes from add-ins like sugar, flavored syrups, and dairy milk, not the coffee itself.
Healthy Alternatives Exist: For those who don't prefer it black, low-carb alternatives include unsweetened nut milks, natural sweeteners like stevia, and healthy fats such as MCT oil.
Packed with Antioxidants: Beyond its macronutrient profile, black coffee is rich in antioxidants that help protect against cell damage and inflammation.
Boosts Metabolism: The caffeine in black coffee can temporarily increase your metabolic rate, aiding in weight management and enhanced energy expenditure.
Improves Mental Focus: Caffeine acts as a central nervous system stimulant, blocking adenosine to increase alertness, concentration, and mood.

The Zero-Carb Profile of Black Coffee

At its core, coffee is a simple, plant-based beverage brewed from water and coffee grounds. The brewing process extracts flavor and caffeine from the beans but leaves behind nearly all the carbohydrates. A standard 8-ounce serving of pure, brewed black coffee contains about 2 calories, almost no protein or fat, and essentially 0 grams of carbohydrates. This makes it an ideal, guilt-free drink for anyone monitoring their carbohydrate intake, including those following a ketogenic diet.

Why Additives are the Real Carb Culprits

While the answer to how many carbs are in 1 cup of black coffee is zero, the answer for a specialty coffee drink is entirely different. Most coffee shop creations, and even simple at-home additions, turn a healthy beverage into a high-carb treat. Sugars, syrups, and milks all contribute significantly to the total carbohydrate count.

Flavored Syrups: Just one pump of a flavored syrup, like vanilla or caramel, can add 5 to 20 grams of sugar (a simple carbohydrate).
Sugars: A single teaspoon of granulated white sugar adds approximately 4 grams of carbohydrates. Multiple teaspoons can quickly turn a zero-carb drink into a carb-heavy one.
Milks: Regular dairy milk contains lactose, a natural sugar. A 16-ounce Starbucks cappuccino made with 2% milk has 14 grams of carbs, while a latte contains even more due to its higher milk content.

Low-Carb Coffee Alternatives and Tips

For those who prefer a less bitter taste, several healthy alternatives allow you to enjoy your coffee without derailing your diet. The key is to be mindful of what you add and choose ingredients that don't pack a sugary punch.

Unsweetened Nut Milks: Almond, coconut, and soy milks offer a creamy texture with a fraction of the carbs found in dairy milk. Always opt for the unsweetened versions to avoid hidden sugars.
Keto-Friendly Sweeteners: Natural, zero-carb sweeteners like liquid stevia or monk fruit can add sweetness without impacting blood sugar levels.
Healthy Fats (Keto Coffee): The "bulletproof" or "keto coffee" trend involves blending black coffee with healthy fats like MCT oil, ghee, or grass-fed butter. This creates a rich, creamy texture and provides energy while keeping carb counts at zero.
Spices and Extracts: A dash of cinnamon, nutmeg, or a few drops of pure vanilla extract can add flavor complexity without any carbs or calories.
Flavored Coffee Beans: Some brands offer naturally flavored coffee beans that provide a hint of taste, such as hazelnut or vanilla, without adding carbs. Always check the label to ensure no sugar or artificial sweeteners were added after roasting.

Comparison of Coffee Additives


Additive	Carb Count (Approx.)	Notes
Pure Black Coffee	0g	Virtually zero carbs, calories, and fat. The base for healthy enjoyment.
1 tsp Sugar	4g	A simple, fast-acting carbohydrate that can quickly add up.
1 tbsp Heavy Cream	0.4g	Low in carbs and high in fat, suitable for keto diets.
1 tbsp Half-and-Half	0.6g	Higher in carbs than heavy cream, but still lower than milk.
8 oz 2% Dairy Milk	12g	Contains lactose, a natural sugar that adds significant carbs.
8 oz Unsweetened Almond Milk	<1g	A creamy, low-carb, dairy-free alternative.
1 Pump Flavored Syrup	5-20g	The biggest source of hidden sugar and carbs in cafe drinks.

The Health Benefits of Black Coffee

Beyond its low-carb status, black coffee is packed with beneficial compounds that offer a range of health advantages. The coffee bean contains powerful antioxidants, and moderate consumption has been linked to several positive health outcomes.

Boosts Metabolism

The caffeine in black coffee can stimulate your metabolic rate, which is the speed at which your body burns calories at rest. This thermogenic effect can contribute to weight management by increasing energy expenditure. Some research suggests caffeine can also aid in fat mobilization, helping the body use stored fat for fuel.

Enhances Mental and Physical Performance

As a natural stimulant, caffeine blocks the neurotransmitter adenosine, which promotes relaxation and sleepiness. In turn, this increases alertness, improves concentration, and reduces feelings of fatigue. For athletes, moderate caffeine intake before a workout has been shown to enhance endurance and performance.

Rich in Antioxidants

Coffee is one of the single biggest sources of antioxidants in many diets. These antioxidants, such as chlorogenic acid, help fight inflammation and protect the body's cells from damage caused by harmful molecules known as free radicals. These compounds are responsible for many of coffee's documented health benefits, from liver protection to potentially reducing the risk of certain cancers.

Conclusion: Savor the Simplicity of Black Coffee

The question of how many carbs are in 1 cup of black coffee is not complicated—the answer is none. Its virtually carb-free nature makes it a perfect beverage for low-carb and ketogenic diets. However, maintaining this nutritional profile requires vigilance against common, carb-loaded additions like sugar, milk, and syrups. By sticking to a simple brew or opting for smart, low-carb alternatives, you can enjoy all the invigorating benefits and rich flavor of black coffee without compromising your dietary goals. For those interested in its broader health benefits, including its antioxidant properties and metabolic-boosting effects, it remains a fantastic, healthy addition to a balanced lifestyle.

For more nutritional information on a wide range of foods and beverages, a resource like the USDA's FoodData Central is a highly reliable source. The information can help you make informed decisions about your daily intake, much like understanding the simple composition of black coffee itself.

Frequently Asked Questions

Yes, pure brewed black coffee contains virtually zero carbohydrates and calories. The minimal amounts of naturally occurring sugars in coffee beans are not significantly extracted during the brewing process.

You can use a variety of low-carb options to enhance flavor, including unsweetened almond or coconut milk, zero-carb natural sweeteners like stevia, or a dash of spices such as cinnamon or nutmeg.

Plain instant coffee generally contains a negligible amount of carbohydrates, similar to brewed black coffee. However, the carb count will rise if you use instant mixes that contain added sugar or milk powders.

Yes, black coffee is perfectly compatible with a ketogenic diet because it has no carbs and does not spike insulin levels. Many people on keto use black coffee, sometimes with added healthy fats, to boost energy and metabolism.

The carb count for milk varies. Regular dairy milk contains about 12 grams of carbs per cup, primarily from lactose. In contrast, unsweetened almond milk has less than 1 gram of carbs per serving.

Yes, flavored syrups and flavor shots commonly used in coffee shops are often laden with sugar. A single pump can add a significant number of grams of carbs and should be avoided on low-carb diets.

For a strict fast, adding milk to coffee is generally considered to break it due to the calories and lactose. For a very lenient fast, a tiny splash might be acceptable, but black coffee is always the safest option to avoid stimulating digestion and insulin response.