How this page turns an egg into a number
Every figure on this page starts from published USDA FoodData Central values for one hundred grams of egg, cooked the way you picked. That per-100g figure is scaled down to the actual weight of your eggs, then multiplied by how many you are eating. Nothing here is estimated from a generic "one egg equals X calories" rule of thumb; it is worked out from the same weight-based data nutrition labels use.
The "egg weight in grams" step matters more than it looks. A raw or boiled large egg is published at 50 g of edible egg (out of its shell), but a fried large egg is published at 46 g, because a little moisture cooks off in the pan, and a scrambled large egg is published at 61 g, because it picks up milk on the way to the plate. Using each preparation's own weight, rather than assuming every cooked egg still weighs exactly 50 g, is what keeps the fried-versus-boiled comparison below honest.
Why a fried egg costs more calories than a boiled one
Per hundred grams, a fried egg comes in at 196 kcal against 155 kcal for a hard-boiled egg and 143 kcal for a poached one, and the gap is not the egg's fault. Boiling and poaching cook an egg in water with nothing added; frying cooks it in a pan that almost always has a little oil or butter in it, and some of that fat is absorbed into the egg as it sets. The fat content confirms it: a fried large egg carries about 15.2 g of fat per hundred grams against roughly 9.5 to 10.6 g for the boiled, poached and raw rows, and fat holds more than double the calories per gram that protein or carbohydrate do. Scrambled eggs sit in between for the same reason, cooked with a splash of milk rather than standing oil, which adds some calories but far less than a fry pan does.
None of that makes fried eggs a food to avoid; it means the calorie difference between preparations is really a calorie difference between cooking fats, not between eggs. Scrambling or poaching instead of frying is one of the more reliable small changes for trimming calories from an egg-heavy breakfast, without changing the egg itself at all.
Where the calories, fat and protein actually live
Crack an egg apart and the two halves are nutritionally almost opposite. Egg white is close to pure protein: about 52 kcal per hundred grams, nearly all of it from protein, with barely a trace of fat. Egg yolk carries the rest: around 322 kcal per hundred grams, most of it fat, along with a meaningful share of the egg's protein too. A large egg's white and yolk add up close to the published whole-egg figures, but not exactly, because USDA measures the whole egg, the white and the yolk as three separate samples rather than deriving one from the other two. Small differences between independently measured foods are normal and not a sign that any of the numbers are wrong.
That splits matters for how you use the rest of a carton. Someone counting fat closely can go a long way on egg whites alone, since the yolk is where almost all of an egg's fat sits; someone after the full nutritional picture, including the fat-soluble vitamins and choline concentrated in the yolk, loses most of that by discarding it.
A short word on egg protein
Egg protein has one of the highest biological values of any common food and has historically been used as the reference protein against which other foods are scored, because the body can use an unusually large share of what it takes in. That is a genuine reason eggs turn up so often in protein-focused diets, separate from the calorie counting this page does. If you want a fuller daily protein target rather than a per-egg figure, the Protein Calculator works that out from your weight and goal.
And the cholesterol question
Eggs, particularly the yolk, are one of the more concentrated dietary sources of cholesterol, and older guidelines set a hard daily limit because of it. That advice has genuinely softened: the current US Dietary Guidelines dropped their specific numeric cholesterol limit in 2015, and UK NHS guidance does not set a cap on how many eggs a healthy person can eat in a week. The science behind the change is that dietary cholesterol has a smaller effect on blood cholesterol for most people than saturated fat does, not that cholesterol has stopped mattering. This page does not track cholesterol in its own figures, and anyone with existing high cholesterol, heart disease or a doctor's specific advice about eggs should follow that advice over a general calculator.
Being honest about egg sizes
USDA's published nutrient figures, and the ones behind this page, are measured for a large egg. There is no separately published "fried medium egg" or "scrambled small egg" dataset to draw on. Instead, this page scales the large-egg weight using the same ratios the USDA's own shell-egg grading standards use between weight classes, small at three-quarters of a large egg's weight, medium at seven-eighths, extra large at one-and-one-eighth, which is a reasonable, stated approximation rather than an independently measured figure for every size and preparation. Treat the size toggle as a solid estimate, not a lab measurement.
Questions people ask
How many calories are in one large boiled egg?
About 78 kcal for one large hard-boiled egg (50 g), using the USDA figure of 155 kcal per hundred grams. A large fried egg runs higher, around 90 kcal, mostly from the added cooking fat.
Why does frying add so many calories?
Because of the oil or butter in the pan, some of which the egg absorbs as it cooks, not because of anything about the egg itself. Boiling and poaching add no fat at all, which is why they come out lowest of the five cooking methods here.
Is egg white or egg yolk healthier?
Neither is simply "healthier"; they do different jobs. Egg white is almost pure protein with very little fat, useful if you are watching fat or calories closely. Egg yolk carries almost all of the egg's fat, but also its fat-soluble vitamins and choline, so removing it trades those nutrients away along with the calories.
Are eggs still bad for cholesterol?
Current guidance is softer than it used to be. The US Dietary Guidelines removed their specific daily cholesterol limit in 2015, and UK guidance does not cap egg intake for a healthy adult, since dietary cholesterol affects most people's blood cholesterol less than saturated fat does. Anyone with existing high cholesterol or heart disease should still follow their doctor's personal advice over general guidance.
How accurate is the size scaling?
It is a reasonable estimate, not a separate measurement. USDA only publishes detailed nutrient data for a large egg, so this page scales that weight for other sizes using the same ratios the USDA uses between its own shell-egg weight classes. Real eggs vary bird to bird regardless of the label on the box.
Why don't the white and yolk numbers add up exactly to the whole egg?
Because USDA measured the whole egg, the white and the yolk as three separate samples, not as one derived from the other two. They land close together, within a gram or two of calories and fat, but small gaps like that are normal between independently measured foods.
How much protein is in eggs compared with other foods?
A large egg carries around 6 to 7 g of protein depending on how it is cooked, and egg protein is unusually well used by the body, which is why it has long served as a reference point for scoring other proteins. For a full daily target based on your weight and goal, the Protein Calculator takes it further.
This tool uses typical published nutrient figures for eggs by cooking method; real eggs vary by bird, feed and exact cooking time. It is not medical or dietetic advice, and it does not track cholesterol. Anyone with a heart condition, high cholesterol or specific dietary advice from a doctor should follow that advice ahead of a calculator.