Tomato Calories Per Gram Calculator

Tomatoes are one of the lowest-calorie foods you can weigh, yet calorie math still trips up meal preppers and macro trackers. A typical raw tomato contains only about 18 calories per 100 grams — roughly 0.18 calories per gram — which makes it a favourite for anyone counting calories, following a low-calorie diet, or building a high-volume meal plan.

This tomato calories per gram calculator does the math for you in seconds. Choose the tomato form you're using — raw, cherry, Roma, cooked, sun-dried, or paste — enter the amount by weight, volume, or piece count, and get an instant calorie estimate along with carbohydrate, protein, fat, and fiber values. It's useful for nutrition students double-checking food labels, dietitians translating serving sizes, and home cooks converting fresh tomato recipes to calorie-controlled portions.

Use the quick-fill portion buttons to start from familiar serving sizes like a cherry tomato, a medium slicing tomato, or one cup of chopped tomato.

🍅 Tomato Calories Per Gram Calculator

Estimate calories in tomatoes by weight, cup measure, or piece count — instantly.

Tomato Type

Amount

Quick portions:

Quick Start

Choose the tomato form you're actually using — raw, cherry, Roma, cooked, tomato paste, or sun-dried — because each one has a different calorie density. Water content changes dramatically when tomatoes are cooked or dried, which shifts the calories per gram even though the base ingredient is the same.

Then enter your amount in grams, ounces, cups of chopped tomato, or whole fruit count. The calculator converts everything to grams first, then applies the per-100-gram calorie and nutrient values for your selected form. If your recipe lists "2 cups diced tomatoes," use the cup unit; if you have a kitchen scale, grams will always give the most accurate result.

Portion presets: a cherry tomato averages 17 g, a small tomato 91 g, a medium tomato 123 g, a large tomato 182 g, and one cup of chopped tomato weighs about 180 g. Tap a preset button to fill the amount field automatically, then hit Calculate Calories.

Worked Examples

Snack of cherry tomatoes. Three cherry tomatoes at 17 g each = 51 g total. Cherry tomatoes have 20 kcal per 100 g, so 51 ÷ 100 × 20 = 10.2 kcal.

Big garden salad. Two cups of chopped raw tomato = 360 g. Raw tomato has 18 kcal per 100 g, so 360 ÷ 100 × 18 = 64.8 kcal for the entire two-cup pile — roughly the same as a single square of chocolate.

Pasta sauce with paste. A 50 g serving of tomato paste (82 kcal per 100 g) contributes 50 ÷ 100 × 82 = 41 kcal, plus about 9.5 g of carbs and 2.1 g of fiber, before any oil or sugar is added to the pan.

How the Calculation Works

Calories scale linearly with weight: calories = weight in grams ÷ 100 × calories per 100 g. A 123 g medium raw tomato therefore gives 123 ÷ 100 × 18 ≈ 22 kcal. Each nutrient — carbohydrates, protein, fat, and fiber — uses the same proportional method, so results stay consistent whether you enter 1 gram or 1 kilogram of tomatoes.

Unit conversions used inside the calculator: 1 ounce = 28.35 g; 1 cup chopped ≈ 180 g; one small tomato ≈ 91 g; one medium tomato ≈ 123 g; one large tomato ≈ 182 g. Whole-fruit weights are averages from common retail sizes, so weighing a specific tomato on a kitchen scale will always be more precise than counting pieces.

Reference Data (per 100 g)

The values below are rounded averages consistent with the USDA FoodData Central database. Cooked and stewed figures assume boiling or steaming without added fat.

Form	Calories	Carbs	Protein	Fat	Fiber
Raw red ripe	18 kcal	3.9 g	0.9 g	0.2 g	1.2 g
Cherry tomatoes	20 kcal	3.9 g	0.9 g	0.2 g	1.2 g
Roma / plum	18 kcal	3.9 g	0.9 g	0.2 g	1.2 g
Cooked / stewed	26 kcal	5.3 g	1.3 g	0.5 g	1.1 g
Tomato paste	82 kcal	18.9 g	4.3 g	0.5 g	4.1 g
Sun-dried	258 kcal	55.8 g	14.1 g	3.0 g	12.3 g

Tips & Common Mistakes

Weigh raw produce raw. Tomatoes lose water when cooked, so cooked tomato has a higher calorie density per gram — 26 kcal per 100 g versus 18 kcal raw. If you weigh after cooking, use the cooked values shown here rather than the raw ones.

Oil-packed sun-dried tomatoes differ. Oil absorbed during packing adds fat and calories — roughly 1 g of oil per 4 g of tomato. Dry-packed sun-dried tomatoes match the table values far more closely, so check the label before logging your portion.

Watch what travels with the tomato. Raw tomatoes are about 0.18 kcal per gram, but a spoonful of olive oil in a sauce adds roughly 120 kcal, and a teaspoon of sugar adds 16 kcal. This calculator covers the tomato itself, not the rest of the recipe.

Frequently Asked Questions

Are tomatoes negative-calorie foods? No. They are extremely low in calories, but the energy your body spends digesting them is far smaller than the calories they provide. Enjoy them freely, but treat them as a smart, high-volume low-calorie choice — not a nutritional loophole.

Why do calorie values differ between sources? Tomato variety, ripeness, water content, and growing conditions all shift nutrient values slightly. The figures here are rounded averages; entries in the USDA FoodData Central database (https://fdc.nal.usda.gov/) may show small differences from brand-specific or regional products.

How accurate is the piece-count method? Whole small, medium, and large tomatoes vary widely — a single "medium" tomato can range from 100 g to 150 g. Piece counts are convenient for quick estimates, but a gram-based entry is always the most reliable option.

Additional Resources

For deeper nutrition data, the USDA FoodData Central database (https://fdc.nal.usda.gov/) provides full nutrient profiles for raw and processed tomato products, and the USDA MyPlate Vegetable Group page (https://www.myplate.gov/eat-healthy/vegetables) explains how tomatoes fit into a balanced diet.