Carbs in tomatoes. The total carbohyrate, sugar, fiber and estimated net carbs (non-fiber carbs) for a variety of types and serving sizes of Cherry Tomatoes is shown below. Get full nutrition facts and other common serving sizes of Grape Tomatoes including 1 oz and 100 g. The number of carbs in tomatoes depends on the size [*]: An average large whole tomato contains 5 grams net carbs; A medium whole tomato has 3.3 grams net carbs; A small whole tomato contains 2.5 grams net carbs; Carbs in cherry tomatoes. There are 4 calories in 1 medium slice of Tomatoes. You can enjoy these tomatoes on keto, too. Carbs in Cherry Tomatoes The favorite choice for the term "Cherry Tomatoes" is 1 cup of Cherry Tomatoes which has about 6 grams of carbohydrate . The total carbohyrate, sugar, fiber and estimated net carbs (non-fiber carbs) for a variety of types and serving sizes of Tomatoes is shown below. In terms of carbs percentage this is 123 % more carbs. Therefore, Tomatoes, sun-dried has 30.76 g more carbs than pasta. What about cherry tomatoes? Get full nutrition facts and other common serving sizes of Tomatoes including 1 grape and 1 thin/small slice. There is 1 calorie in 1 Grape Tomato. Carbs in Tomatoes The favorite choice for the term "Tomatoes" is 1 medium whole Red Tomato which has about 5 grams of carbohydrate .