How much protein is in white bread?

White bread has 8.9 g of protein per 100 g and 2.6 g per 1 slice (29 g). That is 3.3 g of protein per 100 kcal — a modest protein contribution.

Where do these calorie figures come from?

USDA FoodData Central record 174924, “Bread, white, commercially prepared (includes soft bread crumbs)” (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

BreadUSDA SR LegacyFDC 174924

Calories in white bread

USDA FoodData Central record for “Bread, white, commercially prepared (includes soft bread crumbs)” — per 100 g, per every USDA serving size, and next to the other bread rows.

The short answer

White bread: 266 kcal per 100 g. 1 slice (29 g) is 77 kcal with 2.6 g of protein. Source: USDA FoodData Central record 174924, "Bread, white, commercially prepared (includes soft bread crumbs)".

Per 100 g

Nutrient	Per 100 g	Share of energy
Energy	266 kcal	100%
Protein	8.9 g	13%
Fat	3.3 g	11%
Carbohydrate	49.4 g	74%

White bread is 266 kcal per 100 g in USDA FoodData Central (SR Legacy). Of that energy, about 13% comes from protein, 11% from fat and 74% from carbohydrate. That works out to 3.3 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	266	8.9 g	3.3 g	49.4 g
1 slice	29 g	77	2.6 g	1 g	14.3 g
1 oz	28 g	76	2.5 g	0.9 g	14 g
1 cup, crumbs	45 g	120	4 g	1.5 g	22.2 g
1 cup, cubes	35 g	93	3.1 g	1.2 g	17.3 g
1 slice, large	30 g	80	2.7 g	1 g	14.8 g
1 slice crust not eaten	12 g	32	1.1 g	0.4 g	5.9 g
1 slice, thin	20 g	53	1.8 g	0.7 g	9.9 g
1 slice thin, crust not eaten	9 g	24	0.8 g	0.3 g	4.4 g

Compared with other bread

Food	kcal / 100 g	Protein / 100 g	Per serving
White bread	266	8.9 g	77 kcal · 1 slice
Toasted white bread	290	9 g	78 kcal · 1 slice, large
Whole-wheat bread	252	12.5 g	81 kcal · 1 slice
Toasted whole-wheat bread	306	16.3 g	77 kcal · 1 slice

Worth knowing

A standard slice of commercial white bread is about 29 g and 77 kcal. Per 100 g, bread is denser than cooked rice or potato because it holds far less water — the slice, not the loaf, is the unit to log.

Questions about white bread

How many calories are in white bread?: White bread: 266 kcal per 100 g. 1 slice (29 g) is 77 kcal with 2.6 g of protein. Source: USDA FoodData Central record 174924, "Bread, white, commercially prepared (includes soft bread crumbs)".
How much protein is in white bread?: White bread has 8.9 g of protein per 100 g and 2.6 g per 1 slice (29 g). That is 3.3 g of protein per 100 kcal — a modest protein contribution.
Where do these calorie figures come from?: USDA FoodData Central record 174924, “Bread, white, commercially prepared (includes soft bread crumbs)” (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 “white bread” into calorie.one and the app matches this exact record — “Bread, white, commercially prepared (includes soft bread crumbs)” — 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 How accurate is calorie counting, really?.