A single slice of white bread (25g) has just 67 calories, with 2.2g protein and 12.4g carbs, according to USDA FoodData Central. That is less than a medium banana. Yet bread is the first thing people cut when they start losing weight - and one of the first foods they overeat when the restriction snaps.
You don't need to cut it. You need its real numbers. Here is the complete breakdown using USDA data - every common type, per 100g and per piece.
Bread Calories by Type
| Type | Per 100g | Per typical piece |
|---|---|---|
| White | 266 cal | 67 cal per slice (25g) |
| Whole wheat | 252 cal | 81 cal per slice (32g) |
| Sourdough | 272 cal | 84 cal per medium slice (31g) |
| Rye | 259 cal | 83 cal per slice (32g) |
| Bagel, plain | 264 cal | 277 cal per medium bagel (105g) |
| Pita, white | 275 cal | 165 cal per large pita (60g) |
| Flour tortilla | 306 cal | 150 cal per 8-inch tortilla (49g) |
| Corn tortilla | 218 cal | 52 cal per tortilla (24g) |
Source: USDA FoodData Central (SR Legacy and FNDDS).
Notice how little the first column moves. White, whole wheat, sourdough, rye, even a bagel - almost everything sits between 250 and 275 calories per 100g. Bread is bread. What moves is the second column, and that is entirely about the size of the piece.
A "Slice" Is Not a Unit
This is where bread tracking quietly falls apart. A thin sandwich slice of white bread weighs 20g - 53 calories. A thick-cut slice of sourdough weighs 43g - 117 calories (USDA). Both go into your app as "1 slice of bread, toasted," and one of them logs more than double the other.
Whole wheat is the classic illusion here. Per 100g it is actually the lightest of the sliced breads - 252 calories versus 266 for white. But a standard whole wheat slice weighs 32g against white's 25g, so per slice it looks more expensive: 81 versus 67. Nothing about the bread changed; the piece got bigger. It's the same trap that makes brown rice look heavier than white per cup of cooked rice, and it's why the rule from our guide on matching the weight on the scale to the right database entry applies to bread too: grams are the unit, not pieces.
The fix costs ten seconds. Weigh one slice of the loaf you actually buy, log bread in grams, and reuse that number for the life of the loaf. Bread is one of the few foods where the package label usually matches as-is - but only if your slice weighs what the label's slice weighs.
The Bagel Is Four Slices in Disguise
Per 100g, a plain bagel (264 cal) is no richer than sandwich bread. But a medium bagel weighs 105g - 277 calories before anything touches it, roughly four thin slices of bread pressed into one ring. Large bakery bagels reach 131g and 346 calories. A large pita is 165; a 10-inch burrito tortilla is 220. None of these are problems - they are just bigger pieces than the word "bread" suggests, and your log should say so.
What Goes On It Outweighs the Bread
Two slices of white toast: 133 calories. Two tablespoons of peanut butter on top: about 190. Butter, mayo, cream cheese - the spread routinely beats the bread underneath it. When toast gets blamed for a stalled week, the toast was usually carrying something. Log the spread with the same honesty as the slice.
The Bottom Line
Every common bread sits between 218 and 306 calories per 100g (USDA) - the type you choose matters far less than the size of the piece. Pick the bread you like, weigh one slice once, and fit it into your day. Get your daily number from the daily calorie calculator, then put tomorrow's slice on the scale before it hits the toaster. That one weighing replaces every bread rule you've ever been handed.
