A large hard-boiled egg contains about 78 calories. That number shifts depending on egg size, ranging from 54 calories for a small egg up to 90 for a jumbo. Since most cartons in grocery stores contain large eggs, 78 calories is the figure that applies to most people.
Calories by Egg Size
Egg sizes are standardized by weight, so the calorie differences are predictable:
- Small (38 g): 54 calories
- Medium (44 g): 63 calories
- Large (50 g): 78 calories
- Extra-large (56 g): 80 calories
- Jumbo (63 g): 90 calories
If you’re tracking calories closely, the size printed on your egg carton is the number to use. The difference between a medium and a jumbo egg is about 27 calories, which adds up if you eat two or three at a time.
Where the Calories Come From
A whole large egg provides roughly 6.3 grams of protein and about 5 grams of fat. Those macronutrients aren’t split evenly between the white and the yolk. The egg white contains about 17 calories and 3.6 grams of protein, with virtually no fat or cholesterol. It’s mostly protein and water.
The yolk carries the remaining 55 or so calories, along with most of the fat, cholesterol, and nearly all the vitamins and minerals. That includes vitamin D, vitamin B12, choline, and calcium. So while eating only egg whites cuts calories roughly in half, it also strips out most of the nutritional value. For the majority of people, the whole egg is the better choice unless you’re specifically trying to reduce fat or cholesterol intake.
How Eggs Compare to Other Breakfast Proteins
At 78 calories with over 6 grams of protein, a hard-boiled egg is one of the most calorie-efficient protein sources you can eat. A single strip of bacon runs about 43 calories but delivers only 3 grams of protein. A tablespoon of peanut butter has around 95 calories. A cup of Greek yogurt lands near 100 calories with similar protein to two eggs, but often comes with added sugar.
Eggs also score well on satiety, meaning how full they keep you. A study published in the Journal of the American College of Nutrition tested this directly. Women who ate an egg breakfast consumed significantly fewer calories at lunch compared to those who ate a bagel breakfast with the same calorie count. The difference wasn’t small: the egg group ate about 164 fewer calories at lunch. Over the full day, they ate roughly 264 fewer total calories. That gap persisted even into the following morning, with the egg breakfast group consuming about 420 fewer calories across a 36-hour window. The protein and fat in eggs slow digestion, keeping hunger signals quieter for longer.
Does Cooking Method Change the Calories?
Hard boiling doesn’t add or remove calories from an egg because no oil, butter, or other ingredients are involved. You’re cooking the egg in its own shell with nothing but water. That makes hard-boiled eggs one of the lowest-calorie ways to prepare them.
Frying an egg in a tablespoon of butter adds about 100 calories. Scrambling with milk and butter pushes a two-egg serving well past 200 calories. Poaching, like hard boiling, keeps the calorie count unchanged since no fat is added during cooking.
How Many Eggs You Can Eat Per Day
Current dietary guidance supports eating up to one egg per day for healthy adults. For healthy older adults, up to two eggs per day fits within recommended patterns. Vegetarians who rely on eggs as a primary protein source can reasonably eat more than that. These recommendations reflect the shift away from strict cholesterol limits that defined earlier dietary guidelines. The cholesterol in egg yolks (about 186 mg per large egg) raises blood cholesterol less than saturated fat does for most people.
If you have existing heart disease or diabetes, your tolerance for dietary cholesterol may differ. But for the general population, a daily egg is well within healthy eating patterns.
Storing Hard-Boiled Eggs Safely
Hard-boiled eggs keep for about one week in the refrigerator, whether peeled or unpeeled. The key is getting them into the fridge within two hours of cooking. Store them on an inside shelf rather than the door, where temperature fluctuates each time you open the fridge. Peeled eggs can dry out, so keeping them in a sealed container or covered with a damp paper towel helps maintain texture. If an egg smells sulfurous or feels slimy, toss it regardless of how recently you cooked it.