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Calories in a lemon

A typical serving of lemon (1 lemon, 58 g) has about 17 calories. Per 100 g: 29 kcal, 1.1 g protein, 9.3 g carbs, 0.3 g fat. The same 100 g carries 2.8 g of fiber and 2.5 g of sugar. Most of the energy comes from carbohydrate.

Calories by serving size

ServingWeightCalories
1 lemon58 g17 kcal
1 wedge7 g2 kcal
100 g100 g29 kcal

Macros per 100 g

1.1 g
Protein
9.3 g
Carbs
0.3 g
Fat
2.8 g
Fiber
2.5 g
Sugar

Worth knowing

You rarely eat a whole one, and the juice of a full lemon adds only about 11 calories. On the energy-density scale, 29 kcal per 100 g puts lemon at the very low end.

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Frequently asked questions

How many calories are in a lemon?

A typical serving (1 lemon, 58 g) has about 17 calories, and 100 g has 29 kcal. Calories scale with weight, so double the portion means double the number.

How much protein is in a lemon?

There are 1.1 g of protein in 100 g of lemon, which works out to about 0.6 g per serving (1 lemon). Treat it as an energy source rather than a protein source.

How many carbs are in a lemon?

There are 9.3 g of carbohydrate per 100 g of lemon, or about 5 g in 1 lemon (58 g).

Where do these numbers come from?

Every value on this page comes from USDA FoodData Central, entry 167746 (SR Legacy). Serving figures are converted from the per-100-g data, so rounding can shift a total by a calorie or two.

Related foods

Snap a photo of your plate in Joules and the calories and macros for lemon are logged for you.

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A note on accuracy: calculators like this one provide estimates based on population-level formulas — your real needs vary with genetics, muscle mass, medical conditions, and more. Results are for information only and are not medical advice, a diagnosis, or a prescription. Talk to a doctor or registered dietitian before making significant changes to your diet or exercise, especially if you have a health condition, are pregnant, or are under 18.

Nutrition data: USDA FoodData Central, FDC ID 167746 (SR Legacy). Serving calories are computed from the per-100-g values.