How much protein is in unsalted butter?

Unsalted butter has 0.9 g of protein per 100 g and 0.1 g per 1 tbsp (14 g). That is 0.1 g of protein per 100 kcal — essentially not a protein source.

Where do these calorie figures come from?

USDA FoodData Central record 173430, “Butter, without salt” (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

Butter, oils and creamUSDA SR LegacyFDC 173430

Calories in unsalted butter

USDA FoodData Central record for “Butter, without salt” — per 100 g, per every USDA serving size, and next to the other butter, oils and cream rows.

The short answer

Unsalted butter: 717 kcal per 100 g. 1 tbsp (14 g) is 102 kcal with 0.1 g of protein. Source: USDA FoodData Central record 173430, "Butter, without salt".

Per 100 g

Nutrient	Per 100 g	Share of energy
Energy	717 kcal	100%
Protein	0.9 g	0%
Fat	81.1 g	99%
Carbohydrate	0.1 g	0%

Unsalted butter is 717 kcal per 100 g in USDA FoodData Central (SR Legacy). Of that energy, about 0% comes from protein, 99% from fat and 0% from carbohydrate. That works out to 0.1 g of protein per 100 kcal — essentially not a protein source.

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	717	0.9 g	81.1 g	0.1 g
1 pat (1" sq, 1/3" high)	5 g	36	0 g	4.1 g	0 g
1 tbsp	14 g	102	0.1 g	11.5 g	0 g
1 cup	227 g	1628	2 g	184.1 g	0.2 g
1 stick	113 g	810	1 g	91.6 g	0.1 g

Compared with other butter, oils and cream

Food	kcal / 100 g	Protein / 100 g	Per serving
Salted butter	717	0.9 g	102 kcal · 1 tbsp
Unsalted butter	717	0.9 g	102 kcal · 1 tbsp
Olive oil	884	0 g	119 kcal · 1 tablespoon
Coconut oil	892	0 g	121 kcal · 1 tbsp
Heavy whipping cream	340	2.8 g	809 kcal · 1 cup, fluid (yields 2 cups whipped)

Other tables in dairy and egg products

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

Questions about unsalted butter

How many calories are in unsalted butter?: Unsalted butter: 717 kcal per 100 g. 1 tbsp (14 g) is 102 kcal with 0.1 g of protein. Source: USDA FoodData Central record 173430, "Butter, without salt".
How much protein is in unsalted butter?: Unsalted butter has 0.9 g of protein per 100 g and 0.1 g per 1 tbsp (14 g). That is 0.1 g of protein per 100 kcal — essentially not a protein source.
Where do these calorie figures come from?: USDA FoodData Central record 173430, “Butter, without salt” (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 “unsalted butter” into calorie.one and the app matches this exact record — “Butter, without salt” — 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.