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Calories in a slice of pizza, by size and topping

October 21, 2026 · Viral Tandel

Looking for the nutritional information for a slice of pizza gets you a number that is almost meaningless on its own, because the word slice is doing far too much work. The United States Department of Agriculture puts most pizza between 263 and 293 kcal per 100 g no matter what is on it. What USDA also publishes, and what actually decides your figure, is that a slice can weigh anywhere from 51 g to 177 g.

Key takeaways

• Pizza is remarkably consistent per 100 g: 263 to 293 across crusts and toppings.
• A slice is not. USDA weighs them from 51 g (small, thin crust) to 177 g (extra-large, thick crust).
• That is a 3.5 times range in the thing you are counting, against a 10 percent range in the thing most articles talk about.
• Pepperoni against cheese is about 6 percent. One size up in slice is worth several times that.
• Estimate the slice before you worry about the topping.

The figure per 100 g barely moves

Nineteen calories per 100 g separates plain cheese from extra meat on a thick crust. Pizza is, by weight, a very stable food: bread, cheese and a modest amount of topping, in roughly the same proportions whoever makes it.

The slice is where everything happens

The lightest slice and the heaviest slice in USDA's own data are 357 calories apart. Both are one slice. Both would be logged identically by anyone searching for the calories in a slice of pizza and taking the first number they find.

This is the clearest example on the site of why a serving description without a weight is not a measurement. It is the same failure mode as the ounce confusion covered in the chicken breast portion guide: the unit sounds precise and is not.

Thin crust, stuffed crust, and what they really change

Thin crust does not meaningfully lower the figure per 100 g. Extra cheese thin crust is 268 and cheese stuffed crust is 274. Six calories.

What thin crust does is make the slice lighter. A medium thin crust slice is 66 g where a medium stuffed crust slice is 100 g. The saving is real, it is about 97 calories a slice, and it comes entirely from eating less pizza rather than from eating different pizza.

Stuffed crust is the same mechanism pointed the other way. Nobody is being misled; the crust is visibly larger and it weighs more.

Estimating a slice you did not cut

Three things narrow it quickly.

Pizza diameter. A 14 inch pizza has roughly twice the area of a 10 inch one. Cut both into eight, and a slice of the first is about twice the slice of the second.

Crust depth. Thin, regular, thick and stuffed are roughly a progression in slice weight at the same diameter.

Count the slices in the pizza, not just the slices you ate. Two of eight from a large is a very different quantity from two of eight from a personal, and the only way to get this wrong is to not ask.

If the place you ordered from publishes its own nutrition data, use theirs rather than the generic figures here. That is always the better source when it exists, and it is why this site builds calculators from brands' own published data rather than estimating.

For everything else, a photo with the whole pizza in frame gives a size reference that a photo of one slice does not. KalTrack will tell you what size it thinks it is looking at so you can correct it. Point it at the box.

This is general information about published nutrition data, not medical advice. If you are managing a health condition or following a prescribed diet, talk to a clinician or a registered dietitian.