How Many Calories in a Slice of Bread? White vs Whole Wheat

A slice of commercial white bread is about 77 calories and a slice of whole-wheat bread is about 81, by USDA FoodData Central figures using USDA's own slice weights. Yes, that is the right way round: whole wheat is slightly lower per 100 grams, 252 against 266, and slightly higher per slice, because a standard whole-wheat slice weighs 32 grams against white's 29. It is a perfect illustration of the thing that makes bread hard to log. The bread type barely matters. The slice size decides everything, and slice sizes range from 15 grams to 41 grams across the products sitting on the same shelf.

Official USDA numbers, per slice

Using USDA's published slice weight for each bread:

Bread	Slice weight	Calories	Protein	Fiber	Carbs
White	29g	77	2.6g	0.8g	14.3g
Whole wheat	32g	81	4.0g	1.9g	13.7g
Rye	32g	83	2.7g	1.9g	15.5g
Multi-grain	26g	69	3.5g	1.9g	11.3g
White, thin slice	20g	53	1.8g	0.5g	9.9g
Pita, large 6.5 inch	60g	165	5.5g	1.3g	33.4g

Per 100 grams, which is the only fair way to compare the breads themselves:

Bread	Calories	Protein	Fiber
Whole wheat	252	12.5g	6.0g
Rye	259	8.5g	5.8g
Multi-grain	265	13.4g	7.4g
White	266	8.9g	2.7g

The breads are within 6 percent of each other on calories. Where they genuinely differ is fiber and protein: whole wheat carries more than double the fiber of white, and multi-grain carries nearly three times as much. That, not calories, is the real argument for brown bread.

Slice size is the whole game

USDA publishes six different slice weights for the same white bread, because the market genuinely sells that much variation: very thin at 15g, thin at 20g, standard at 25g, the common commercial slice at 29g, and large at 30g. That is a 53-calorie range for one word.

So "two slices of bread" is anywhere from 106 to 154 calories depending on the loaf, and neither end is wrong. A sandwich on thin-sliced sandwich bread and the same sandwich on a bakery sourdough differ by more than 100 calories before a single filling goes on. If you want one thing to check, read the grams per slice on your own bag, then stop thinking about it: your loaf has one number and it does not change week to week.

Does toasting add calories?

No. Toasting drives off water, which is why USDA's toasted entries look higher per 100 grams: toasted white is 290 against 266. Nothing was added. The same slice simply weighs less after toasting, so its calories are packed into fewer grams. USDA reflects this with a lighter slice weight for the toasted entry, 22g against 29g.

The practical answer: log the slice, not the toast. A slice of bread is about 77 calories whether it goes in the toaster or not. What changes the number is what you put on it, which is where the calories in almost every bread meal actually live.

What bread costs once it is a sandwich

Sandwich	Components	Total
Peanut butter	2 white slices (154) + 2 tbsp peanut butter (191)	345
PB and jelly	2 white slices (154) + peanut butter (191) + jam (56)	401
Buttered toast, 2 slices	2 white slices (154) + 2 tsp butter (68)	222
Plain turkey and mustard	2 whole-wheat slices (162) + 3 oz turkey breast (90)	252

Bread is 38 percent of the peanut butter sandwich and 62 percent of the buttered toast. This is the useful mental model: bread is a modest, predictable base that is almost never the reason a meal is expensive. The spread is. Two tablespoons of peanut butter outweigh both slices holding it, as the numbers in our peanut butter guide show.

How I stopped guessing at bread

Bread was the food that taught me database logging was going to fail for me. Searching "bread" in a traditional tracker returns a wall of near-identical entries, dozens of them, each with a slightly different slice weight, and there is no way to know which one matches the loaf in my kitchen. So you pick one, and you have just introduced a permanent unknown error into every sandwich you will ever log.

The fix turned out to be embarrassingly simple: I read the bag once. My loaf says 43 grams per slice, which is heavier than USDA's commercial standard, so my sandwiches start at about 114 calories of bread rather than 154. Now I log "sandwich on my usual bread" in Nouri and the estimate reflects a real slice instead of an average of a hundred loaves. The breakdown separates bread from filling, so when a sandwich comes back higher than I expected I can see instantly whether the bread or the mayonnaise did it. That per-item visibility is the whole reason I built the app the way I did. Nouri is iPhone (iOS only), and you can try it free.

FAQ

How many calories in a slice of bread?

About 77 for a standard 29g slice of commercial white bread, per USDA data. The realistic range across loaves is 53 to 110, driven almost entirely by slice weight.

How many calories in 2 slices of bread?

About 154 for white and 162 for whole wheat. Check your own bag's grams per slice, since thin-sliced loaves land nearer 106 for two.

Is whole wheat bread lower in calories than white?

Per 100 grams, slightly: 252 against 266. Per slice, usually not, because whole-wheat slices are heavier, 32g against 29g, which puts a slice at 81 against 77. Choose it for fiber and protein, not for calories.

How many calories in whole wheat bread?

About 81 per 32g slice, with 4.0g of protein and 1.9g of fiber. That is 252 calories per 100 grams.

Does toasting bread add calories?

No. Toasting removes water only. USDA's toasted figures look higher per 100 grams because the slice weighs less after toasting, not because energy was added.

How many calories in sourdough bread?

USDA does not publish a separate sourdough entry in SR Legacy, so the honest answer is to use your loaf's label. Bakery sourdough slices are often 40g to 60g, which puts them at roughly 110 to 165 each.

Which bread has the most fiber?

Of the breads USDA lists here, multi-grain at 7.4g per 100 grams, then whole wheat at 6.0g and rye at 5.8g. White trails at 2.7g.

How many calories in a pita?

About 165 for a large 6.5-inch pita at 60g, and about 77 for a small 4-inch. Pitas carry very little fat, 0.7g for the large.

Is bread bad for weight loss?

No. At roughly 77 calories a slice it fits most targets easily; what causes trouble is that bread is a delivery vehicle for dense spreads and fillings. Set the target first as in Calorie Counting 101, then decide what goes on the slice.

How many carbs in a slice of bread?

About 14.3g for white and 13.7g for whole wheat per slice. Whole wheat comes in slightly lower on carbs despite the heavier slice, because more of its weight is fiber and protein.

How many calories in a bread roll or bun?

USDA does not give one answer, because rolls range from 30g dinner rolls to 100g burger buns. Weigh one or read the package: at roughly 2.7 calories per gram for most plain wheat breads, grams times 2.7 is a serviceable estimate.

Should I weigh my bread?

Once, then never again. Weigh a single slice from your usual loaf, write the number down, and every sandwich after that is settled. This is the cheapest accuracy win in tracking, and it is the same logic we apply to restaurant meals.

Read your own bag once, then log the sandwich as one sentence in Nouri and let it split the bread from what is on it. The dense half of most bread meals is covered in our peanut butter guide, and the foundations are in Calorie Counting 101.

Sources

• USDA FoodData Central, SR Legacy: Bread, white, commercially prepared (FDC 174924); Bread, whole-wheat, commercially prepared (FDC 172688); Bread, rye (FDC 172684); Bread, multi-grain (FDC 168013); Bread, pita, white, enriched (FDC 174915); Bread, white, toasted (FDC 174925), fdc.nal.usda.gov (checked September 27, 2026)
• Slice weights are USDA's own published household measures for each bread; per-slice values calculated from USDA per-100g figures times those weights
• Peanut butter, jam, butter, and turkey figures from USDA SR Legacy records cited in our peanut butter guide