How Many Carbs in a Tomato? Exact Counts by Type

A medium raw tomato (123g) contains approximately 4.8 grams of total carbohydrates, with 1.5 grams of dietary fiber resulting in 3.3 grams of net carbs. This makes tomatoes an excellent low-carb vegetable option for various dietary plans including keto, diabetes management, and weight loss programs.

Understanding the precise carbohydrate content in tomatoes helps you make informed dietary choices without sacrificing flavor or nutrition. Whether you're tracking macros for weight management, following a specific diet like keto or diabetic meal planning, or simply curious about your food's nutritional profile, knowing exactly how many carbs are in a tomato provides valuable insight for your daily eating decisions.

Tomato Carbohydrate Breakdown by Variety and Size

The carbohydrate content in tomatoes varies slightly depending on the variety, ripeness, and serving size. Based on the most recent USDA FoodData Central database (2023), here's a detailed breakdown of carb counts across common tomato types:

Tomato Type	Typical Serving Size	Total Carbs	Dietary Fiber	Net Carbs	Sugars
Medium raw tomato	123g	4.8g	1.5g	3.3g	2.8g
Roma tomato	62g	2.7g	1.0g	1.7g	1.6g
Cherry tomatoes	149g (1 cup)	6.8g	2.2g	4.6g	4.2g
Beefsteak tomato	182g	7.1g	2.2g	4.9g	4.1g
Tomato juice (unsalted)	248g (1 cup)	10.0g	1.7g	8.3g	6.0g

Source: USDA FoodData Central, National Nutrient Database for Standard Reference

How Tomato Carbs Fit Into Your Diet

Tomatoes contain primarily simple sugars like glucose and fructose, along with dietary fiber that affects how your body processes these carbohydrates. The glycemic index of tomatoes is relatively low at approximately 15, making them suitable for blood sugar management. This low glycemic impact explains why tomatoes remain a staple in Mediterranean diets, which have been associated with reduced risk of type 2 diabetes according to research published in the American Journal of Clinical Nutrition.

When tracking carbohydrates for specific dietary needs, understanding the difference between total carbs and net carbs is essential. Net carbs (total carbs minus fiber) represent the carbohydrates that actually affect your blood sugar levels. For most medium tomatoes, this means approximately 3.3 grams of net carbs rather than the total 4.8 grams.

Tomato Nutrition Evolution: A Brief Timeline

Nutritional understanding of tomatoes has evolved significantly over time. In the 1950s, early nutritional analyses focused primarily on vitamin content, with carbohydrate measurements being less precise. By the 1980s, standardized laboratory techniques improved carbohydrate quantification. The current USDA FoodData Central database represents the most accurate measurements to date, using advanced chromatography methods to distinguish between different carbohydrate types.

This progression in measurement accuracy explains why older references might cite slightly different carb values for tomatoes. Modern nutritional science recognizes that factors like growing conditions, ripeness, and variety significantly impact the exact carbohydrate composition.

Practical Applications for Different Dietary Needs

Understanding tomato carbohydrate content helps you incorporate this versatile vegetable into various dietary approaches:

• Keto diets: With only 3.3g net carbs per medium tomato, they fit comfortably within most keto carb limits (typically 20-50g net carbs daily)
• Diabetes management: The low glycemic index and fiber content make tomatoes an excellent choice for blood sugar control
• Weight loss: At just 22 calories per medium tomato with high water content, they provide volume and nutrition with minimal calories
• General health: The combination of carbohydrates, fiber, and nutrients supports digestive health and overall wellness

Common Misconceptions About Tomato Carbohydrates

Several myths persist about tomato carbs that deserve clarification. Some believe that all carbohydrates in vegetables should be avoided, but the natural sugars in tomatoes come packaged with valuable nutrients and fiber. Others mistakenly think that cooking tomatoes significantly increases their carb content, when in reality, cooking primarily concentrates existing nutrients by removing water.

It's also important to distinguish between fresh tomatoes and processed tomato products. Tomato sauce, ketchup, and sun-dried tomatoes have significantly higher carb concentrations per serving due to water removal and sometimes added sugars. For example, 2 tablespoons of ketchup contains about 4 grams of sugar, whereas a medium tomato contains approximately 2.8 grams of natural sugars.

Maximizing Tomato Benefits in Your Meal Planning

To incorporate tomatoes effectively into your diet while managing carbohydrate intake:

• Measure portions when following strict carb limits
• Pair tomatoes with healthy fats like olive oil to enhance absorption of fat-soluble nutrients
• Choose fresh tomatoes over processed varieties when minimizing carbs is a priority
• Consider the time of day—some find tomatoes better tolerated earlier in the day
• Track your personal response to tomatoes if you have specific metabolic concerns

Remember that individual responses to carbohydrates can vary based on metabolism, activity level, and overall health status. Consulting with a registered dietitian can provide personalized guidance for your specific needs.

Frequently Asked Questions

How many carbs are in a small tomato?

A small tomato (approximately 85g) contains about 3.3 grams of total carbohydrates, with 1.0 gram of dietary fiber, resulting in 2.3 grams of net carbs. This makes small tomatoes an excellent low-carb snack option.

Are tomatoes high in sugar compared to other vegetables?

Tomatoes contain natural sugars but are relatively low compared to many other vegetables. With approximately 2.8 grams of sugar per medium tomato, they contain less sugar than carrots, beets, or corn. The sugar content in tomatoes is balanced by fiber and nutrients, making them a healthy choice.

Do different colored tomatoes have different carb counts?

While there are slight variations, different colored tomatoes (red, yellow, orange) have very similar carbohydrate profiles. Yellow and orange varieties may contain marginally more natural sugars, but the difference is minimal—typically less than 0.5g per medium tomato. The nutritional benefits across colors are comparable.

How do cooking methods affect tomato carbohydrate content?

Cooking tomatoes doesn't significantly change their total carbohydrate content, but it does concentrate carbs by removing water. For example, 1 cup of raw cherry tomatoes (149g) has 6.8g total carbs, while the same volume of cooked tomatoes would have slightly higher carb density due to reduced water content. Roasting or sun-drying dramatically increases carb concentration per volume.

Can I eat tomatoes on a keto diet?

Yes, tomatoes can be included in a keto diet in moderation. A medium tomato contains only 3.3g net carbs, which fits within most keto carb limits (typically 20-50g net carbs daily). To stay within your carb budget, measure portions and account for tomatoes in your daily carb count, especially if following a strict keto protocol.