In this article
Portion and source review: 10/26/2026. Text prepared with AI assistance from the indicated sources. No independent clinical review. General information, not an individual meal plan.
Short answer
To assess tonic water, check the carbohydrate information on the label of the product and package you have. The table below gives values per 100 g. Without knowing the drink’s density, you cannot use these values to calculate the carbohydrates in a can from its volume in ml.
If the label states carbohydrates per 100 ml, multiply that value by the volume in ml divided by 100. The carbohydrate portion calculator does this calculation using the same unit. Check the zero version data separately. This calculation does not determine a recommended amount.
How much carbohydrate does tonic water have?
| Food | Total carbohydrate (g) | Fiber (g) |
|---|---|---|
| Soft drink, tonic water type | 8.0 | NA |
| Soft drink, cola type | 8.7 | NA |
| Coconut water | 5.3 | 0.1 |
TACO: NA = Not applicable.
Tonic water is close to cola soft drink (8.7 g) and above coconut water (5.3 g).
And zero tonic water?
It replaces sugar with sweeteners, and carbohydrates depend on the label. Worth noting what WHO said in 2023: it does not recommend using non-caloric sweeteners to control weight; the recommendation does not apply to those who already have diabetes. Details are in zero-sugar soda on the ketogenic diet.
In drinks
The Harvard Nutrition Source notes that most keto programs restrict beverages with added sweeteners, such as cocktails and mixers with syrup and juice. A regular tonic water in the glass counts toward that.
Tonic water is not sparkling water
Tonic water is a soft drink with sugar; sparkling water is just water with carbon dioxide. See sparkling water on the ketogenic diet.
If you have diabetes or take medication, discuss any change with your doctor. Before deciding, read the risks and precautions of keto.
Sources
- Harvard T.H. Chan School of Public Health, The Nutrition Source: Diet Review: Ketogenic Diet for Weight Loss
- TACO: Brazilian Food Composition Table, 4th revised and expanded edition (NEPA/Unicamp)
- World Health Organization (2023): WHO advises not to use non-sugar sweeteners for weight control
Mariana is passionate about a healthy lifestyle.
