What energy drinks have Ace-K in them?

December 15, 2025 •

3 min read

Over one-third of adults in the U.S. consume energy drinks regularly, and for many of them, sugar content is a primary concern. To provide a low-calorie alternative, many popular sugar-free or diet energy drinks utilize acesulfame potassium, also known as Ace-K. This calorie-free artificial sweetener is often combined with others, such as sucralose, to achieve a more balanced taste profile.

Quick Summary

Acesulfame potassium (Ace-K) is a common ingredient in many zero-sugar and diet energy drinks, providing sweetness without calories. Brands like Red Bull, Monster, and Rockstar use Ace-K, typically combined with other sweeteners like sucralose. Checking product labels is the most reliable method for identifying its presence in specific varieties.

Key Points

Prevalence of Ace-K: Acesulfame potassium is a common artificial sweetener found in many sugar-free and diet energy drinks, including major brands.
Major Brands Using Ace-K: Red Bull (Sugarfree and Zero), Monster (Zero Ultra, Absolutely Zero), and Rockstar (Pure Zero) are well-known examples of drinks that contain Ace-K.
Blended for Taste: Ace-K is almost always blended with other sweeteners, such as sucralose, to counteract its potential bitter aftertaste and create a more sugar-like flavor.
Zero-Calorie Sweetener: As a calorie-free ingredient, Ace-K allows energy drink manufacturers to offer low or zero-calorie versions of their popular products.
Check Labels: The most reliable way to confirm the presence of Ace-K is by reading the ingredients label on the specific can, as formulations can vary by product and region.
Ace-K's Purpose: The use of Ace-K and other artificial sweeteners is a core strategy for energy drink brands to meet the growing demand for sugar-free options.

Common Energy Drink Brands Using Ace-K

When seeking out low-calorie or sugar-free energy drinks, consumers will often encounter Acesulfame Potassium (Ace-K) on the ingredients list. This sweetener is a popular choice for manufacturers because it is heat-stable and helps to reduce the overall calorie count of the product. Several of the biggest names in the energy drink market have formulations that include this sweetener. Its use is almost always in conjunction with another sweetener, most commonly sucralose, to balance the flavor profile, as Ace-K can have a slightly bitter aftertaste on its own.

Red Bull

Red Bull is one of the most recognizable brands to prominently feature Ace-K in its sugar-free options. The company explicitly states on its website and cans that it uses a combination of sucralose and acesulfame K to sweeten its low-calorie beverages.

Red Bull Sugarfree: This is the brand's flagship sugar-free product, and it contains Ace-K.
Red Bull Editions Sugarfree: Many of the flavor variations, such as the Pink Edition Sugarfree and Winter Edition Sugarfree, also use acesulfame K and sucralose as their primary sweeteners.
Red Bull Zero: While different in taste from the Sugarfree variant, Red Bull Zero also relies on a mix of sweeteners, including Ace-K, to achieve its specific flavor without sugar.

Monster Energy

Monster Energy offers a wide array of flavors, and its zero-sugar versions are among the most popular. A key part of achieving the signature Monster taste without sugar is the use of Ace-K, along with other sweeteners.

Monster Zero Ultra: This well-known sugar-free variety uses a combination of acesulfame K, sucralose, and erythritol to deliver its crisp citrus flavor.
Monster Energy Ultra Red: This specific flavor also lists acesulfame K as a sweetening agent.
Monster Absolutely Zero: As the name suggests, this is a zero-calorie option that relies on artificial sweeteners, including Ace-K.

Rockstar Energy

Rockstar has been in the sugar-free energy drink market for decades and has consistently used Ace-K in its diet and zero-sugar formulations.

Rockstar Pure Zero: The Pure Zero line, including flavors like Punched, prominently features acesulfame potassium on its ingredients list.
Diet Rockstar: Older formulations, like the original Diet Rockstar, were among the first to popularize the combination of Ace-K and sucralose for a lower-calorie product.

Other Brands and the Importance of Label Reading

While the major players are reliable sources, many smaller or newer energy drink brands also include Ace-K. For example, Kill Cliff has noted that its sugar-free products use Ace-K. Products such as Mother Energy Drink's Zero Sugar Original also list acesulfame potassium and sucralose. Given the constant evolution of product formulas, the most accurate way to verify a drink's sweetener content is to always check the ingredients label before purchasing.

Comparison of Major Zero-Sugar Energy Drinks Containing Ace-K


Brand	Product	Sweeteners	Key Flavor Notes	Calories (Approx. per 16 oz)	Contains Ace-K?
Red Bull	Sugarfree	Sucralose, Acesulfame K	Original Red Bull flavor profile, but sugar-free	10	Yes
Monster Energy	Zero Ultra	Erythritol, Sucralose, Acesulfame K	Light citrus, crisp finish	10	Yes
Rockstar	Pure Zero Punched	Acesulfame K, Sucralose, Erythritol	Fruit punch	20	Yes
Mother	Zero Sugar Original	Acesulfame Potassium, Sucralose	Standard energy drink flavor	<5	Yes
Bang	Keto Coffee Mocha Madness	Sucralose, Acesulfame K	Coffee, mocha	15	Yes

The Role of Acesulfame Potassium in Energy Drink Formulations

Acesulfame potassium is not just a sweetener; its properties make it a valuable tool for beverage manufacturers. At 200 times sweeter than table sugar, a very small amount can achieve the desired sweetness level. However, its slightly bitter taste is why it is almost always paired with other sweeteners like sucralose or aspartame, creating a more rounded and palatable flavor that closely mimics sugar. Ace-K's stability under heat also makes it an excellent choice for products with a long shelf life. For consumers, the main benefit is the ability to enjoy a sweet-tasting beverage with no added calories from sugar.

Conclusion

Acesulfame potassium, or Ace-K, is a prevalent artificial sweetener used in the energy drink industry, particularly in sugar-free and diet formulations. Brands like Red Bull, Monster, and Rockstar consistently use Ace-K, typically in combination with sucralose, to deliver a sweet flavor with few to no calories. As more consumers seek out zero-sugar options, Ace-K continues to be a staple ingredient. However, consumers should always consult the specific ingredients list on the can, as formulations can change. This simple step ensures that anyone looking to identify energy drinks containing Ace-K can do so accurately and make an informed decision based on their dietary preferences.

Frequently Asked Questions

Ace-K is an abbreviation for acesulfame potassium, a calorie-free, artificial sweetener that is approximately 200 times sweeter than sugar.

Energy drink manufacturers use Ace-K to provide sweetness without adding the calories or sugar content found in standard formulations. It is also heat-stable, giving products a longer shelf life.

No, not all sugar-free energy drinks contain Ace-K. Some brands use other sweeteners like stevia, monk fruit, or aspartame instead. Checking the product label is essential to confirm the specific ingredients.

Ace-K is commonly blended with other artificial sweeteners, most notably sucralose. This combination helps to create a more balanced flavor and masks any potential bitter aftertaste that Ace-K can have on its own.

Ace-K is primarily used in sugar-free and diet versions of energy drinks to reduce the calorie count. Regular versions are sweetened with sugar, glucose, and other caloric sweeteners.

To determine if an energy drink contains Ace-K, you must read the ingredients label. It will be listed either as "acesulfame potassium" or "acesulfame K".

While regulatory bodies like the FDA have deemed Ace-K safe for consumption, some studies have raised questions about its long-term effects on gut health and insulin production. Individuals with specific health concerns should consult their physician.