How much protein is in flaxseed?

Flaxseed has 18.3 g of protein per 100 g and 1.9 g per 1 tbsp, whole (10 g). That is 3.4 g of protein per 100 kcal — a modest protein contribution.

Where do these calorie figures come from?

USDA FoodData Central record 169414, “Seeds, flaxseed” (SR Legacy, FDC SR Legacy 2018-04 + FNDDS 2024-10-31). Energy is USDA nutrient 1008 (Energy, kcal); protein, fat and carbohydrate are read from the same record. USDA data is in the public domain, and the FDC ID above links straight to it.

All foods

SeedsUSDA SR LegacyFDC 169414

Calories in flaxseed

USDA FoodData Central record for “Seeds, flaxseed” — per 100 g, per every USDA serving size, and next to the other seeds rows.

The short answer

Flaxseed: 534 kcal per 100 g. 1 tbsp, whole (10 g) is 55 kcal with 1.9 g of protein. Source: USDA FoodData Central record 169414, "Seeds, flaxseed".

Per 100 g

Nutrient	Per 100 g	Share of energy
Energy	534 kcal	100%
Protein	18.3 g	13%
Fat	42.2 g	67%
Carbohydrate	28.9 g	20%

Flaxseed is 534 kcal per 100 g in USDA FoodData Central (SR Legacy). Of that energy, about 13% comes from protein, 67% from fat and 20% from carbohydrate. That works out to 3.4 g of protein per 100 kcal — a modest protein contribution.

Per serving

The serving sizes USDA lists for this record, priced from the per-100 g figures above. Nothing here is rounded to a “portion” — the gram weight next to each label is what the calories are computed from.

Serving	Weight	Calories	Protein	Fat	Carbs
100 g	100 g	534	18.3 g	42.2 g	28.9 g
1 tbsp, whole	10 g	55	1.9 g	4.3 g	3 g
1 cup, whole	168 g	897	30.7 g	70.9 g	48.6 g
1 tbsp, ground	7 g	37	1.3 g	3 g	2 g
1 tsp, whole	3.4 g	18	0.6 g	1.4 g	1 g
1 tsp, ground	2.5 g	13	0.5 g	1.1 g	0.7 g

Compared with other seeds

Food	kcal / 100 g	Protein / 100 g	Per serving
Chia seeds	486	16.5 g	138 kcal · 1 oz
Flaxseed	534	18.3 g	55 kcal · 1 tbsp, whole
Sunflower seeds	584	20.8 g	269 kcal · 1 cup, with hulls, edible yield

Other tables in nut and seed products

The same numbers for the foods this one usually shares a plate — or a shopping list — with.

Calories in almonds579 kcal / 100 g

Questions about flaxseed

How many calories are in flaxseed?: Flaxseed: 534 kcal per 100 g. 1 tbsp, whole (10 g) is 55 kcal with 1.9 g of protein. Source: USDA FoodData Central record 169414, "Seeds, flaxseed".
How much protein is in flaxseed?: Flaxseed has 18.3 g of protein per 100 g and 1.9 g per 1 tbsp, whole (10 g). That is 3.4 g of protein per 100 kcal — a modest protein contribution.
Where do these calorie figures come from?: USDA FoodData Central record 169414, “Seeds, flaxseed” (SR Legacy, FDC SR Legacy 2018-04 + FNDDS 2024-10-31). Energy is USDA nutrient 1008 (Energy, kcal); protein, fat and carbohydrate are read from the same record. USDA data is in the public domain, and the FDC ID above links straight to it.

How calorie.one logs it

Type “flaxseed” into calorie.one and the app matches this exact record — “Seeds, flaxseed” — estimates the grams, and shows the line with its USDA label. You correct the amount; the per-100 g figure is never guessed. That split between recognition and arithmetic is the whole methodology. For the numbers in context, read Calories in olive oil, butter and cooking fats.