A medium raw tomato (about 123 grams) contains roughly 22 calories. That makes tomatoes one of the lowest-calorie whole foods you can eat, thanks to a water content of around 95%. But the exact number shifts depending on the variety and how the tomato is prepared.
Calories by Tomato Variety
Not all tomatoes are the same size, so their calorie counts vary quite a bit at the individual level. Here’s what you’re working with for common varieties:
- Grape tomato (8g): 1 calorie
- Cherry tomato (17g): 3 calories
- Roma tomato (62g): 11 calories
- Beefsteak tomato (182g, about 3 inches across): 33 calories
On a per-gram basis, though, these varieties are all very similar. The differences come down to size. A cup of cherry tomatoes (about 149 grams, or roughly 9 tomatoes) adds up to only 27 calories, making them an easy snack that barely registers on your daily intake.
What’s Actually in Those Calories
Tomatoes are almost entirely carbohydrates, with very little protein or fat. One cup of chopped raw tomato contains about 7 grams of carbohydrates, 1.6 grams of protein, and just 0.4 grams of fat. Those carbohydrates are split fairly evenly between fructose and glucose, with almost no sucrose. A ripe red tomato has roughly 1.5 grams each of fructose and glucose.
You also get about 1.5 grams of fiber from an average-sized tomato, or 1.2 grams per 100-gram serving. Combined with all that water, the fiber helps explain why tomatoes feel satisfying relative to their calorie count. They take up a lot of space in your stomach without adding much energy.
Glycemic Impact
Raw tomatoes have a low glycemic index, falling below 55 on the standard scale. Their glycemic load is even lower because there simply isn’t much sugar present in a typical serving. For anyone watching blood sugar, tomatoes are about as neutral as a food gets.
How Cooking and Processing Change the Count
Raw tomatoes are low in calories, but processing removes water and concentrates everything, including the calories. The differences are dramatic.
A cup of cooked tomatoes (240g) contains about 43 calories. That’s a modest increase from raw, mostly because cooking softens the structure and you can fit more tomato into a cup. Sun-dried tomatoes are a different story entirely. One cup of sun-dried tomatoes (54g) packs 139 calories, more than five times the calories of the same volume of fresh cherry tomatoes. Tomato paste is similarly concentrated. If you’re scooping sun-dried tomatoes onto a salad or spreading paste on bread, you’re dealing with a much more calorie-dense food than the fresh version.
Canned diced tomatoes and jarred sauces fall somewhere in between, though added ingredients like oil or sugar can push the count higher. Checking the label matters more for processed tomato products than for the fresh fruit itself.
Tomatoes Compared to Other Produce
At roughly 18 calories per 100 grams, raw tomatoes sit near the bottom of the calorie scale even among vegetables. Cucumbers and lettuce are slightly lower (around 12 to 15 calories per 100g), while carrots and bell peppers are slightly higher (roughly 25 to 40 calories per 100g). Fruits like apples and bananas carry 50 to 90 calories per 100 grams, so tomatoes are far closer to leafy greens than to most fruit in terms of energy density.
This low calorie density is almost entirely due to water. When you remove that water (as in sun-dried tomatoes), the calorie count per gram jumps to levels comparable to dried fruit. The tomato itself hasn’t changed. You’re just eating it in a much more concentrated form.